{-# LANGUAGE TypeApplications    #-}
{-# LANGUAGE DeriveFunctor       #-}
{-# LANGUAGE FlexibleContexts    #-}
{-# LANGUAGE RankNTypes          #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TypeFamilies        #-}
{-# LANGUAGE ViewPatterns        #-}
{-# LANGUAGE DisambiguateRecordFields #-}
{-# LANGUAGE MultiWayIf                 #-}
{-
(c) The GRASP/AQUA Project, Glasgow University, 1992-1998

Renaming of patterns

Basically dependency analysis.

Handles @Match@, @GRHSs@, @HsExpr@, and @Qualifier@ datatypes.  In
general, all of these functions return a renamed thing, and a set of
free variables.
-}
module GHC.Rename.Pat (-- main entry points
              rnPat, rnPats, rnBindPat,

              NameMaker, applyNameMaker,     -- a utility for making names:
              localRecNameMaker, topRecNameMaker,  --   sometimes we want to make local names,
                                             --   sometimes we want to make top (qualified) names.
              isTopRecNameMaker,

              rnHsRecFields, HsRecFieldContext(..),
              rnHsRecUpdFields,

              -- CpsRn monad
              CpsRn, liftCps, liftCpsWithCont,

              -- Literals
              rnLit, rnOverLit,
             ) where

-- ENH: thin imports to only what is necessary for patterns

import GHC.Prelude

import {-# SOURCE #-} GHC.Rename.Expr ( rnLExpr )
import {-# SOURCE #-} GHC.Rename.Splice ( rnSplicePat )

import GHC.Hs
import GHC.Tc.Errors.Types
import GHC.Tc.Utils.Monad
import GHC.Tc.Utils.TcMType ( hsOverLitName )
import GHC.Rename.Env
import GHC.Rename.Fixity
import GHC.Rename.Utils    ( newLocalBndrRn, bindLocalNames
                           , warnUnusedMatches, newLocalBndrRn
                           , checkUnusedRecordWildcard
                           , checkDupNames, checkDupAndShadowedNames
                           , wrapGenSpan, genHsApps, genLHsVar, genHsIntegralLit, warnForallIdentifier )
import GHC.Rename.HsType
import GHC.Builtin.Names

import GHC.Types.Name
import GHC.Types.Name.Set
import GHC.Types.Name.Reader
import GHC.Types.Unique.Set

import GHC.Types.Basic
import GHC.Types.SourceText
import GHC.Utils.Misc
import GHC.Data.FastString ( uniqCompareFS )
import GHC.Data.List.SetOps( removeDups )
import GHC.Utils.Outputable
import GHC.Utils.Panic.Plain
import GHC.Types.SrcLoc
import GHC.Types.Literal   ( inCharRange )
import GHC.Types.GREInfo   ( ConInfo(..), conInfoFields )
import GHC.Builtin.Types   ( nilDataCon )
import GHC.Core.DataCon
import qualified GHC.LanguageExtensions as LangExt

import Control.Monad       ( when, ap, guard )
import Data.Foldable
import Data.Function       ( on )
import Data.Functor.Identity ( Identity (..) )
import qualified Data.List.NonEmpty as NE
import Data.Maybe
import Data.Ratio


{-
*********************************************************
*                                                      *
        The CpsRn Monad
*                                                      *
*********************************************************

Note [CpsRn monad]
~~~~~~~~~~~~~~~~~~
The CpsRn monad uses continuation-passing style to support this
style of programming:

        do { ...
           ; ns <- bindNames rs
           ; ...blah... }

   where rs::[RdrName], ns::[Name]

The idea is that '...blah...'
  a) sees the bindings of ns
  b) returns the free variables it mentions
     so that bindNames can report unused ones

In particular,
    mapM rnPatAndThen [p1, p2, p3]
has a *left-to-right* scoping: it makes the binders in
p1 scope over p2,p3.
-}

newtype CpsRn b = CpsRn { forall b.
CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
unCpsRn :: forall r. (b -> RnM (r, FreeVars))
                                            -> RnM (r, FreeVars) }
        deriving ((forall a b. (a -> b) -> CpsRn a -> CpsRn b)
-> (forall a b. a -> CpsRn b -> CpsRn a) -> Functor CpsRn
forall a b. a -> CpsRn b -> CpsRn a
forall a b. (a -> b) -> CpsRn a -> CpsRn b
forall (f :: * -> *).
(forall a b. (a -> b) -> f a -> f b)
-> (forall a b. a -> f b -> f a) -> Functor f
$cfmap :: forall a b. (a -> b) -> CpsRn a -> CpsRn b
fmap :: forall a b. (a -> b) -> CpsRn a -> CpsRn b
$c<$ :: forall a b. a -> CpsRn b -> CpsRn a
<$ :: forall a b. a -> CpsRn b -> CpsRn a
Functor)
        -- See Note [CpsRn monad]

instance Applicative CpsRn where
    pure :: forall a. a -> CpsRn a
pure a
x = (forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn a
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\a -> RnM (r, FreeVars)
k -> a -> RnM (r, FreeVars)
k a
x)
    <*> :: forall a b. CpsRn (a -> b) -> CpsRn a -> CpsRn b
(<*>) = CpsRn (a -> b) -> CpsRn a -> CpsRn b
forall (m :: * -> *) a b. Monad m => m (a -> b) -> m a -> m b
ap

instance Monad CpsRn where
  (CpsRn forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
m) >>= :: forall a b. CpsRn a -> (a -> CpsRn b) -> CpsRn b
>>= a -> CpsRn b
mk = (forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\b -> RnM (r, FreeVars)
k -> (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
m (\a
v -> CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
forall b.
CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
unCpsRn (a -> CpsRn b
mk a
v) b -> RnM (r, FreeVars)
k))

runCps :: CpsRn a -> RnM (a, FreeVars)
runCps :: forall a. CpsRn a -> RnM (a, FreeVars)
runCps (CpsRn forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
m) = (a -> RnM (a, FreeVars)) -> RnM (a, FreeVars)
forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
m (\a
r -> (a, FreeVars) -> RnM (a, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (a
r, FreeVars
emptyFVs))

liftCps :: RnM a -> CpsRn a
liftCps :: forall a. RnM a -> CpsRn a
liftCps RnM a
rn_thing = (forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn a
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\a -> RnM (r, FreeVars)
k -> RnM a
rn_thing RnM a -> (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
forall a b.
IOEnv (Env TcGblEnv TcLclEnv) a
-> (a -> IOEnv (Env TcGblEnv TcLclEnv) b)
-> IOEnv (Env TcGblEnv TcLclEnv) b
forall (m :: * -> *) a b. Monad m => m a -> (a -> m b) -> m b
>>= a -> RnM (r, FreeVars)
k)

liftCpsFV :: RnM (a, FreeVars) -> CpsRn a
liftCpsFV :: forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV RnM (a, FreeVars)
rn_thing = (forall r. (a -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn a
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\a -> RnM (r, FreeVars)
k -> do { (a
v,FreeVars
fvs1) <- RnM (a, FreeVars)
rn_thing
                                     ; (r
r,FreeVars
fvs2) <- a -> RnM (r, FreeVars)
k a
v
                                     ; (r, FreeVars) -> RnM (r, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (r
r, FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2) })

liftCpsWithCont :: (forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)) -> CpsRn b
liftCpsWithCont :: forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
liftCpsWithCont = (forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn

wrapSrcSpanCps :: (a -> CpsRn b) -> LocatedA a -> CpsRn (LocatedA b)
-- Set the location, and also wrap it around the value returned
wrapSrcSpanCps :: forall a b. (a -> CpsRn b) -> LocatedA a -> CpsRn (LocatedA b)
wrapSrcSpanCps a -> CpsRn b
fn (L SrcSpanAnnA
loc a
a)
  = (forall r. (LocatedA b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn (LocatedA b)
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\LocatedA b -> RnM (r, FreeVars)
k -> SrcSpanAnnA -> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
setSrcSpanA SrcSpanAnnA
loc (RnM (r, FreeVars) -> RnM (r, FreeVars))
-> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a b. (a -> b) -> a -> b
$
                 CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
forall b.
CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
unCpsRn (a -> CpsRn b
fn a
a) ((b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
forall a b. (a -> b) -> a -> b
$ \b
v ->
                 LocatedA b -> RnM (r, FreeVars)
k (SrcSpanAnnA -> b -> LocatedA b
forall l e. l -> e -> GenLocated l e
L SrcSpanAnnA
loc b
v))

lookupConCps :: LocatedN RdrName -> CpsRn (LocatedN Name)
lookupConCps :: GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
lookupConCps GenLocated (SrcAnn NameAnn) RdrName
con_rdr
  = (forall r.
 (LocatedN Name -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn (LocatedN Name)
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\LocatedN Name -> RnM (r, FreeVars)
k -> do { LocatedN Name
con_name <- GenLocated (SrcAnn NameAnn) RdrName -> TcRn (LocatedN Name)
forall ann.
GenLocated (SrcSpanAnn' ann) RdrName
-> TcRn (GenLocated (SrcSpanAnn' ann) Name)
lookupLocatedOccRnConstr GenLocated (SrcAnn NameAnn) RdrName
con_rdr
                    ; (r
r, FreeVars
fvs) <- LocatedN Name -> RnM (r, FreeVars)
k LocatedN Name
con_name
                    ; (r, FreeVars) -> RnM (r, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (r
r, FreeVars -> Name -> FreeVars
addOneFV FreeVars
fvs (LocatedN Name -> Name
forall l e. GenLocated l e -> e
unLoc LocatedN Name
con_name)) })
    -- We add the constructor name to the free vars
    -- See Note [Patterns are uses]

{-
Note [Patterns are uses]
~~~~~~~~~~~~~~~~~~~~~~~~
Consider
  module Foo( f, g ) where
  data T = T1 | T2

  f T1 = True
  f T2 = False

  g _ = T1

Arguably we should report T2 as unused, even though it appears in a
pattern, because it never occurs in a constructed position.
See #7336.
However, implementing this in the face of pattern synonyms would be
less straightforward, since given two pattern synonyms

  pattern P1 <- P2
  pattern P2 <- ()

we need to observe the dependency between P1 and P2 so that type
checking can be done in the correct order (just like for value
bindings). Dependencies between bindings is analyzed in the renamer,
where we don't know yet whether P2 is a constructor or a pattern
synonym. So for now, we do report conid occurrences in patterns as
uses.

*********************************************************
*                                                      *
        Name makers
*                                                      *
*********************************************************

Externally abstract type of name makers,
which is how you go from a RdrName to a Name
-}

data NameMaker
  = LamMk       -- Lambdas
      Bool      -- True <=> report unused bindings
                --   (even if True, the warning only comes out
                --    if -Wunused-matches is on)

  | LetMk       -- Let bindings, incl top level
                -- Do *not* check for unused bindings
      TopLevelFlag
      MiniFixityEnv

topRecNameMaker :: MiniFixityEnv -> NameMaker
topRecNameMaker :: MiniFixityEnv -> NameMaker
topRecNameMaker MiniFixityEnv
fix_env = TopLevelFlag -> MiniFixityEnv -> NameMaker
LetMk TopLevelFlag
TopLevel MiniFixityEnv
fix_env

isTopRecNameMaker :: NameMaker -> Bool
isTopRecNameMaker :: NameMaker -> Bool
isTopRecNameMaker (LetMk TopLevelFlag
TopLevel MiniFixityEnv
_) = Bool
True
isTopRecNameMaker NameMaker
_ = Bool
False

localRecNameMaker :: MiniFixityEnv -> NameMaker
localRecNameMaker :: MiniFixityEnv -> NameMaker
localRecNameMaker MiniFixityEnv
fix_env = TopLevelFlag -> MiniFixityEnv -> NameMaker
LetMk TopLevelFlag
NotTopLevel MiniFixityEnv
fix_env

matchNameMaker :: HsMatchContext a -> NameMaker
matchNameMaker :: forall a. HsMatchContext a -> NameMaker
matchNameMaker HsMatchContext a
ctxt = Bool -> NameMaker
LamMk Bool
report_unused
  where
    -- Do not report unused names in interactive contexts
    -- i.e. when you type 'x <- e' at the GHCi prompt
    report_unused :: Bool
report_unused = case HsMatchContext a
ctxt of
                      StmtCtxt (HsDoStmt HsDoFlavour
GhciStmtCtxt) -> Bool
False
                      -- also, don't warn in pattern quotes, as there
                      -- is no RHS where the variables can be used!
                      HsMatchContext a
ThPatQuote            -> Bool
False
                      HsMatchContext a
_                     -> Bool
True

newPatLName :: NameMaker -> LocatedN RdrName -> CpsRn (LocatedN Name)
newPatLName :: NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
newPatLName NameMaker
name_maker rdr_name :: GenLocated (SrcAnn NameAnn) RdrName
rdr_name@(L SrcAnn NameAnn
loc RdrName
_)
  = do { Name
name <- NameMaker -> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn Name
newPatName NameMaker
name_maker GenLocated (SrcAnn NameAnn) RdrName
rdr_name
       ; LocatedN Name -> CpsRn (LocatedN Name)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (SrcAnn NameAnn -> Name -> LocatedN Name
forall l e. l -> e -> GenLocated l e
L SrcAnn NameAnn
loc Name
name) }

newPatName :: NameMaker -> LocatedN RdrName -> CpsRn Name
newPatName :: NameMaker -> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn Name
newPatName (LamMk Bool
report_unused) GenLocated (SrcAnn NameAnn) RdrName
rdr_name
  = (forall r. (Name -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn Name
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\ Name -> RnM (r, FreeVars)
thing_inside ->
        do { GenLocated (SrcAnn NameAnn) RdrName -> RnM ()
warnForallIdentifier GenLocated (SrcAnn NameAnn) RdrName
rdr_name
           ; Name
name <- GenLocated (SrcAnn NameAnn) RdrName -> RnM Name
newLocalBndrRn GenLocated (SrcAnn NameAnn) RdrName
rdr_name
           ; (r
res, FreeVars
fvs) <- [Name] -> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a. [Name] -> RnM a -> RnM a
bindLocalNames [Name
name] (Name -> RnM (r, FreeVars)
thing_inside Name
name)
           ; Bool -> RnM () -> RnM ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when Bool
report_unused (RnM () -> RnM ()) -> RnM () -> RnM ()
forall a b. (a -> b) -> a -> b
$ [Name] -> FreeVars -> RnM ()
warnUnusedMatches [Name
name] FreeVars
fvs
           ; (r, FreeVars) -> RnM (r, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (r
res, Name
name Name -> FreeVars -> FreeVars
`delFV` FreeVars
fvs) })

newPatName (LetMk TopLevelFlag
is_top MiniFixityEnv
fix_env) GenLocated (SrcAnn NameAnn) RdrName
rdr_name
  = (forall r. (Name -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn Name
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\ Name -> RnM (r, FreeVars)
thing_inside ->
        do { GenLocated (SrcAnn NameAnn) RdrName -> RnM ()
warnForallIdentifier GenLocated (SrcAnn NameAnn) RdrName
rdr_name
           ; Name
name <- case TopLevelFlag
is_top of
                       TopLevelFlag
NotTopLevel -> GenLocated (SrcAnn NameAnn) RdrName -> RnM Name
newLocalBndrRn GenLocated (SrcAnn NameAnn) RdrName
rdr_name
                       TopLevelFlag
TopLevel    -> GenLocated (SrcAnn NameAnn) RdrName -> RnM Name
newTopSrcBinder GenLocated (SrcAnn NameAnn) RdrName
rdr_name
           ; [Name] -> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a. [Name] -> RnM a -> RnM a
bindLocalNames [Name
name] (RnM (r, FreeVars) -> RnM (r, FreeVars))
-> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a b. (a -> b) -> a -> b
$
                 -- Do *not* use bindLocalNameFV here;
                 --   see Note [View pattern usage]
                 -- For the TopLevel case
                 --   see Note [bindLocalNames for an External name]
             MiniFixityEnv -> [Name] -> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a. MiniFixityEnv -> [Name] -> RnM a -> RnM a
addLocalFixities MiniFixityEnv
fix_env [Name
name] (RnM (r, FreeVars) -> RnM (r, FreeVars))
-> RnM (r, FreeVars) -> RnM (r, FreeVars)
forall a b. (a -> b) -> a -> b
$
             Name -> RnM (r, FreeVars)
thing_inside Name
name })

{- Note [bindLocalNames for an External name]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In the TopLevel case, the use of bindLocalNames here is somewhat
suspicious because it binds a top-level External name in the
LocalRdrEnv.  c.f. Note [LocalRdrEnv] in GHC.Types.Name.Reader.

However, this only happens when renaming the LHS (only) of a top-level
pattern binding.  Even though this only the LHS, we need to bring the
binder into scope in the pattern itself in case the binder is used in
subsequent view patterns.  A bit bizarre, something like
  (x, Just y <- f x) = e

Anyway, bindLocalNames does work, and the binding only exists for the
duration of the pattern; then the top-level name is added to the
global env before going on to the RHSes (see GHC.Rename.Module).

Note [View pattern usage]
~~~~~~~~~~~~~~~~~~~~~~~~~
Consider
  let (r, (r -> x)) = x in ...
Here the pattern binds 'r', and then uses it *only* in the view pattern.
We want to "see" this use, and in let-bindings we collect all uses and
report unused variables at the binding level. So we must use bindLocalNames
here, *not* bindLocalNameFV.  #3943.


Note [Don't report shadowing for pattern synonyms]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
There is one special context where a pattern doesn't introduce any new binders -
pattern synonym declarations. Therefore we don't check to see if pattern
variables shadow existing identifiers as they are never bound to anything
and have no scope.

Without this check, there would be quite a cryptic warning that the `x`
in the RHS of the pattern synonym declaration shadowed the top level `x`.

```
x :: ()
x = ()

pattern P x = Just x
```

See #12615 for some more examples.

Note [Handling overloaded and rebindable patterns]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Overloaded paterns and rebindable patterns are desugared in the renamer
using the HsPatExpansion mechanism detailed in:
Note [Rebindable syntax and HsExpansion]
The approach is similar to that of expressions, which is further detailed
in Note [Handling overloaded and rebindable constructs] in GHC.Rename.Expr.

Here are the patterns that are currently desugared in this way:

* ListPat (list patterns [p1,p2,p3])
  When (and only when) OverloadedLists is on, desugar to a view pattern:
    [p1, p2, p3]
  ==>
    toList -> [p1, p2, p3]
              ^^^^^^^^^^^^ built-in (non-overloaded) list pattern
  NB: the type checker and desugarer still see ListPat,
      but to them it always means the built-in list pattern.
  See Note [Desugaring overloaded list patterns] below for more details.

We expect to add to this list as we deal with more patterns via the expansion
mechanism.

Note [Desugaring overloaded list patterns]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
If OverloadedLists is enabled, we desugar a list pattern to a view pattern:

  [p1, p2, p3]
==>
  toList -> [p1, p2, p3]

This happens directly in the renamer, using the HsPatExpansion mechanism
detailed in Note [Rebindable syntax and HsExpansion].

Note that we emit a special view pattern: we additionally keep track of an
inverse to the pattern.
See Note [Invertible view patterns] in GHC.Tc.TyCl.PatSyn for details.

== Wrinkle ==

This is all fine, except in one very specific case:
  - when RebindableSyntax is off,
  - and the type being matched on is already a list type.

In this case, it is undesirable to desugar an overloaded list pattern into
a view pattern. To illustrate, consider the following program:

> {-# LANGUAGE OverloadedLists #-}
>
> f []    = True
> f (_:_) = False

Without any special logic, the pattern `[]` is desugared to `(toList -> [])`,
whereas `(_:_)` remains a constructor pattern. This implies that the argument
of `f` is necessarily a list (even though `OverloadedLists` is enabled).
After desugaring the overloaded list pattern `[]`, and type-checking, we obtain:

> f :: [a] -> Bool
> f (toList -> []) = True
> f (_:_)          = False

The pattern match checker then warns that the pattern `[]` is not covered,
as it isn't able to look through view patterns.
We can see that this is silly: as we are matching on a list, `toList` doesn't
actually do anything. So we ignore it, and desugar the pattern to an explicit
list pattern, instead of a view pattern.

Note however that this is not necessarily sound, because it is possible to have
a list `l` such that `toList l` is not the same as `l`.
This can happen with an overlapping instance, such as the following:

instance {-# OVERLAPPING #-} IsList [Int] where
  type Item [Int] = Int
  toList = reverse
  fromList = reverse

We make the assumption that no such instance exists, in order to avoid worsening
pattern-match warnings (see #14547).

*********************************************************
*                                                      *
        External entry points
*                                                      *
*********************************************************

There are various entry points to renaming patterns, depending on
 (1) whether the names created should be top-level names or local names
 (2) whether the scope of the names is entirely given in a continuation
     (e.g., in a case or lambda, but not in a let or at the top-level,
      because of the way mutually recursive bindings are handled)
 (3) whether the a type signature in the pattern can bind
        lexically-scoped type variables (for unpacking existential
        type vars in data constructors)
 (4) whether we do duplicate and unused variable checking
 (5) whether there are fixity declarations associated with the names
     bound by the patterns that need to be brought into scope with them.

 Rather than burdening the clients of this module with all of these choices,
 we export the three points in this design space that we actually need:
-}

-- ----------- Entry point 1: rnPats -------------------
-- Binds local names; the scope of the bindings is entirely in the thing_inside
--   * allows type sigs to bind type vars
--   * local namemaker
--   * unused and duplicate checking
--   * no fixities
rnPats :: Traversable f
       => HsMatchContext GhcRn -- for error messages
       -> f (LPat GhcPs)
       -> (f (LPat GhcRn) -> RnM (a, FreeVars))
       -> RnM (a, FreeVars)
rnPats :: forall (f :: * -> *) a.
Traversable f =>
HsMatchContext GhcRn
-> f (LPat GhcPs)
-> (f (LPat GhcRn) -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnPats HsMatchContext GhcRn
ctxt f (LPat GhcPs)
pats f (LPat GhcRn) -> RnM (a, FreeVars)
thing_inside
  = do  { (GlobalRdrEnv, LocalRdrEnv)
envs_before <- TcRn (GlobalRdrEnv, LocalRdrEnv)
getRdrEnvs

          -- (1) rename the patterns, bringing into scope all of the term variables
          -- (2) then do the thing inside.
        ; CpsRn (f (GenLocated SrcSpanAnnA (Pat GhcRn)))
-> forall r.
   (f (GenLocated SrcSpanAnnA (Pat GhcRn)) -> RnM (r, FreeVars))
   -> RnM (r, FreeVars)
forall b.
CpsRn b -> forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars)
unCpsRn (NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
forall (f :: * -> *).
Traversable f =>
NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen (HsMatchContext GhcRn -> NameMaker
forall a. HsMatchContext a -> NameMaker
matchNameMaker HsMatchContext GhcRn
ctxt) f (LPat GhcPs)
pats) ((f (GenLocated SrcSpanAnnA (Pat GhcRn)) -> RnM (a, FreeVars))
 -> RnM (a, FreeVars))
-> (f (GenLocated SrcSpanAnnA (Pat GhcRn)) -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
forall a b. (a -> b) -> a -> b
$ \ f (GenLocated SrcSpanAnnA (Pat GhcRn))
pats' -> do
        { -- Check for duplicated and shadowed names
          -- Must do this *after* renaming the patterns
          -- See Note [Collect binders only after renaming] in GHC.Hs.Utils
          -- Because we don't bind the vars all at once, we can't
          --    check incrementally for duplicates;
          -- Nor can we check incrementally for shadowing, else we'll
          --    complain *twice* about duplicates e.g. f (x,x) = ...
          --
          -- See Note [Don't report shadowing for pattern synonyms]
        ; let bndrs :: [IdP GhcRn]
bndrs = CollectFlag GhcRn -> [LPat GhcRn] -> [IdP GhcRn]
forall p. CollectPass p => CollectFlag p -> [LPat p] -> [IdP p]
collectPatsBinders CollectFlag GhcRn
forall p. CollectFlag p
CollNoDictBinders (f (GenLocated SrcSpanAnnA (Pat GhcRn))
-> [GenLocated SrcSpanAnnA (Pat GhcRn)]
forall a. f a -> [a]
forall (t :: * -> *) a. Foldable t => t a -> [a]
toList f (GenLocated SrcSpanAnnA (Pat GhcRn))
pats')
        ; SDoc -> RnM () -> RnM ()
forall a. SDoc -> TcM a -> TcM a
addErrCtxt SDoc
doc_pat (RnM () -> RnM ()) -> RnM () -> RnM ()
forall a b. (a -> b) -> a -> b
$
          if HsMatchContext GhcRn -> Bool
forall p. HsMatchContext p -> Bool
isPatSynCtxt HsMatchContext GhcRn
ctxt
             then [Name] -> RnM ()
checkDupNames [IdP GhcRn]
[Name]
bndrs
             else (GlobalRdrEnv, LocalRdrEnv) -> [Name] -> RnM ()
checkDupAndShadowedNames (GlobalRdrEnv, LocalRdrEnv)
envs_before [IdP GhcRn]
[Name]
bndrs
        ; f (LPat GhcRn) -> RnM (a, FreeVars)
thing_inside f (LPat GhcRn)
f (GenLocated SrcSpanAnnA (Pat GhcRn))
pats' } }
  where
    doc_pat :: SDoc
doc_pat = String -> SDoc
forall doc. IsLine doc => String -> doc
text String
"In" SDoc -> SDoc -> SDoc
forall doc. IsLine doc => doc -> doc -> doc
<+> HsMatchContext GhcRn -> SDoc
forall p.
(Outputable (IdP (NoGhcTc p)), UnXRec (NoGhcTc p)) =>
HsMatchContext p -> SDoc
pprMatchContext HsMatchContext GhcRn
ctxt
{-# SPECIALIZE rnPats :: HsMatchContext GhcRn -> [LPat GhcPs] -> ([LPat GhcRn] -> RnM (a, FreeVars)) -> RnM (a, FreeVars) #-}
{-# SPECIALIZE rnPats :: HsMatchContext GhcRn -> Identity (LPat GhcPs) -> (Identity (LPat GhcRn) -> RnM (a, FreeVars)) -> RnM (a, FreeVars) #-}

rnPat :: HsMatchContext GhcRn -- for error messages
      -> LPat GhcPs
      -> (LPat GhcRn -> RnM (a, FreeVars))
      -> RnM (a, FreeVars)     -- Variables bound by pattern do not
                               -- appear in the result FreeVars
rnPat :: forall a.
HsMatchContext GhcRn
-> LPat GhcPs
-> (LPat GhcRn -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnPat HsMatchContext GhcRn
ctxt LPat GhcPs
pat LPat GhcRn -> RnM (a, FreeVars)
thing_inside
  = HsMatchContext GhcRn
-> Identity (LPat GhcPs)
-> (Identity (LPat GhcRn) -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
forall (f :: * -> *) a.
Traversable f =>
HsMatchContext GhcRn
-> f (LPat GhcPs)
-> (f (LPat GhcRn) -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnPats HsMatchContext GhcRn
ctxt (GenLocated SrcSpanAnnA (Pat GhcPs)
-> Identity (GenLocated SrcSpanAnnA (Pat GhcPs))
forall a. a -> Identity a
Identity LPat GhcPs
GenLocated SrcSpanAnnA (Pat GhcPs)
pat) (LPat GhcRn -> RnM (a, FreeVars)
GenLocated SrcSpanAnnA (Pat GhcRn) -> RnM (a, FreeVars)
thing_inside (GenLocated SrcSpanAnnA (Pat GhcRn) -> RnM (a, FreeVars))
-> (Identity (GenLocated SrcSpanAnnA (Pat GhcRn))
    -> GenLocated SrcSpanAnnA (Pat GhcRn))
-> Identity (GenLocated SrcSpanAnnA (Pat GhcRn))
-> RnM (a, FreeVars)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. Identity (GenLocated SrcSpanAnnA (Pat GhcRn))
-> GenLocated SrcSpanAnnA (Pat GhcRn)
forall a. Identity a -> a
runIdentity)

applyNameMaker :: NameMaker -> LocatedN RdrName -> RnM (LocatedN Name)
applyNameMaker :: NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName -> TcRn (LocatedN Name)
applyNameMaker NameMaker
mk GenLocated (SrcAnn NameAnn) RdrName
rdr = do { (LocatedN Name
n, FreeVars
_fvs) <- CpsRn (LocatedN Name) -> RnM (LocatedN Name, FreeVars)
forall a. CpsRn a -> RnM (a, FreeVars)
runCps (NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
newPatLName NameMaker
mk GenLocated (SrcAnn NameAnn) RdrName
rdr)
                           ; LocatedN Name -> TcRn (LocatedN Name)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return LocatedN Name
n }

-- ----------- Entry point 2: rnBindPat -------------------
-- Binds local names; in a recursive scope that involves other bound vars
--      e.g let { (x, Just y) = e1; ... } in ...
--   * does NOT allows type sig to bind type vars
--   * local namemaker
--   * no unused and duplicate checking
--   * fixities might be coming in
rnBindPat :: NameMaker
          -> LPat GhcPs
          -> RnM (LPat GhcRn, FreeVars)
   -- Returned FreeVars are the free variables of the pattern,
   -- of course excluding variables bound by this pattern

rnBindPat :: NameMaker -> LPat GhcPs -> RnM (LPat GhcRn, FreeVars)
rnBindPat NameMaker
name_maker LPat GhcPs
pat = CpsRn (GenLocated SrcSpanAnnA (Pat GhcRn))
-> RnM (GenLocated SrcSpanAnnA (Pat GhcRn), FreeVars)
forall a. CpsRn a -> RnM (a, FreeVars)
runCps (NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
name_maker LPat GhcPs
pat)

{-
*********************************************************
*                                                      *
        The main event
*                                                      *
*********************************************************
-}

-- ----------- Entry point 3: rnLPatAndThen -------------------
-- General version: parameterized by how you make new names

rnLPatsAndThen :: Traversable f => NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen :: forall (f :: * -> *).
Traversable f =>
NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen NameMaker
mk = (GenLocated SrcSpanAnnA (Pat GhcPs)
 -> CpsRn (GenLocated SrcSpanAnnA (Pat GhcRn)))
-> f (GenLocated SrcSpanAnnA (Pat GhcPs))
-> CpsRn (f (GenLocated SrcSpanAnnA (Pat GhcRn)))
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
forall (m :: * -> *) a b. Monad m => (a -> m b) -> f a -> m (f b)
mapM (NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk)
  -- Despite the map, the monad ensures that each pattern binds
  -- variables that may be mentioned in subsequent patterns in the list

--------------------
-- The workhorse
rnLPatAndThen :: NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen :: NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
nm LPat GhcPs
lpat = (Pat GhcPs -> CpsRn (Pat GhcRn))
-> GenLocated SrcSpanAnnA (Pat GhcPs)
-> CpsRn (GenLocated SrcSpanAnnA (Pat GhcRn))
forall a b. (a -> CpsRn b) -> LocatedA a -> CpsRn (LocatedA b)
wrapSrcSpanCps (NameMaker -> Pat GhcPs -> CpsRn (Pat GhcRn)
rnPatAndThen NameMaker
nm) LPat GhcPs
GenLocated SrcSpanAnnA (Pat GhcPs)
lpat

rnPatAndThen :: NameMaker -> Pat GhcPs -> CpsRn (Pat GhcRn)
rnPatAndThen :: NameMaker -> Pat GhcPs -> CpsRn (Pat GhcRn)
rnPatAndThen NameMaker
_  (WildPat XWildPat GhcPs
_)   = Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XWildPat GhcRn -> Pat GhcRn
forall p. XWildPat p -> Pat p
WildPat XWildPat GhcRn
NoExtField
noExtField)
rnPatAndThen NameMaker
mk (ParPat XParPat GhcPs
x LHsToken "(" GhcPs
lpar LPat GhcPs
pat LHsToken ")" GhcPs
rpar) =
  do { GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
     ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XParPat GhcRn
-> LHsToken "(" GhcRn
-> LPat GhcRn
-> LHsToken ")" GhcRn
-> Pat GhcRn
forall p.
XParPat p -> LHsToken "(" p -> LPat p -> LHsToken ")" p -> Pat p
ParPat XParPat GhcPs
XParPat GhcRn
x LHsToken "(" GhcPs
LHsToken "(" GhcRn
lpar LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat' LHsToken ")" GhcPs
LHsToken ")" GhcRn
rpar) }
rnPatAndThen NameMaker
mk (LazyPat XLazyPat GhcPs
_ LPat GhcPs
pat) = do { GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
                                     ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XLazyPat GhcRn -> LPat GhcRn -> Pat GhcRn
forall p. XLazyPat p -> LPat p -> Pat p
LazyPat XLazyPat GhcRn
NoExtField
noExtField LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat') }
rnPatAndThen NameMaker
mk (BangPat XBangPat GhcPs
_ LPat GhcPs
pat) = do { GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
                                     ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XBangPat GhcRn -> LPat GhcRn -> Pat GhcRn
forall p. XBangPat p -> LPat p -> Pat p
BangPat XBangPat GhcRn
NoExtField
noExtField LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat') }
rnPatAndThen NameMaker
mk (VarPat XVarPat GhcPs
x (L SrcAnn NameAnn
l RdrName
rdr))
    = do { SrcSpan
loc <- RnM SrcSpan -> CpsRn SrcSpan
forall a. RnM a -> CpsRn a
liftCps RnM SrcSpan
getSrcSpanM
         ; Name
name <- NameMaker -> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn Name
newPatName NameMaker
mk (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcAnn NameAnn
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
loc) RdrName
rdr)
         ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XVarPat GhcRn -> LIdP GhcRn -> Pat GhcRn
forall p. XVarPat p -> LIdP p -> Pat p
VarPat XVarPat GhcPs
XVarPat GhcRn
x (SrcAnn NameAnn -> Name -> LocatedN Name
forall l e. l -> e -> GenLocated l e
L SrcAnn NameAnn
l Name
name)) }
     -- we need to bind pattern variables for view pattern expressions
     -- (e.g. in the pattern (x, x -> y) x needs to be bound in the rhs of the tuple)

rnPatAndThen NameMaker
mk (SigPat XSigPat GhcPs
_ LPat GhcPs
pat HsPatSigType (NoGhcTc GhcPs)
sig)
  -- When renaming a pattern type signature (e.g. f (a :: T) = ...), it is
  -- important to rename its type signature _before_ renaming the rest of the
  -- pattern, so that type variables are first bound by the _outermost_ pattern
  -- type signature they occur in. This keeps the type checker happy when
  -- pattern type signatures happen to be nested (#7827)
  --
  -- f ((Just (x :: a) :: Maybe a)
  -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~^       `a' is first bound here
  -- ~~~~~~~~~~~~~~~^                   the same `a' then used here
  = do { HsPatSigType GhcRn
sig' <- HsPatSigType GhcPs -> CpsRn (HsPatSigType GhcRn)
rnHsPatSigTypeAndThen HsPatSigType (NoGhcTc GhcPs)
HsPatSigType GhcPs
sig
       ; GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XSigPat GhcRn
-> LPat GhcRn -> HsPatSigType (NoGhcTc GhcRn) -> Pat GhcRn
forall p. XSigPat p -> LPat p -> HsPatSigType (NoGhcTc p) -> Pat p
SigPat XSigPat GhcRn
NoExtField
noExtField LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat' HsPatSigType (NoGhcTc GhcRn)
HsPatSigType GhcRn
sig' ) }
  where
    rnHsPatSigTypeAndThen :: HsPatSigType GhcPs -> CpsRn (HsPatSigType GhcRn)
    rnHsPatSigTypeAndThen :: HsPatSigType GhcPs -> CpsRn (HsPatSigType GhcRn)
rnHsPatSigTypeAndThen HsPatSigType GhcPs
sig = (forall r.
 (HsPatSigType GhcRn -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn (HsPatSigType GhcRn)
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
liftCpsWithCont (HsPatSigTypeScoping
-> HsDocContext
-> HsPatSigType GhcPs
-> (HsPatSigType GhcRn -> RnM (r, FreeVars))
-> RnM (r, FreeVars)
forall a.
HsPatSigTypeScoping
-> HsDocContext
-> HsPatSigType GhcPs
-> (HsPatSigType GhcRn -> RnM (a, FreeVars))
-> RnM (a, FreeVars)
rnHsPatSigType HsPatSigTypeScoping
AlwaysBind HsDocContext
PatCtx HsPatSigType GhcPs
sig)

rnPatAndThen NameMaker
mk (LitPat XLitPat GhcPs
x HsLit GhcPs
lit)
  | HsString XHsString GhcPs
src FastString
s <- HsLit GhcPs
lit
  = do { Bool
ovlStr <- RnM Bool -> CpsRn Bool
forall a. RnM a -> CpsRn a
liftCps (Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedStrings)
       ; if Bool
ovlStr
         then NameMaker -> Pat GhcPs -> CpsRn (Pat GhcRn)
rnPatAndThen NameMaker
mk
                           (LocatedAn NoEpAnns (HsOverLit GhcPs)
-> Maybe (SyntaxExpr GhcPs) -> EpAnn [AddEpAnn] -> Pat GhcPs
mkNPat (HsOverLit GhcPs -> LocatedAn NoEpAnns (HsOverLit GhcPs)
forall a an. a -> LocatedAn an a
noLocA (SourceText -> FastString -> HsOverLit GhcPs
mkHsIsString XHsString GhcPs
SourceText
src FastString
s))
                                      Maybe NoExtField
Maybe (SyntaxExpr GhcPs)
forall a. Maybe a
Nothing EpAnn [AddEpAnn]
forall a. EpAnn a
noAnn)
         else CpsRn (Pat GhcRn)
normal_lit }
  | Bool
otherwise = CpsRn (Pat GhcRn)
normal_lit
  where
    normal_lit :: CpsRn (Pat GhcRn)
normal_lit = do { RnM () -> CpsRn ()
forall a. RnM a -> CpsRn a
liftCps (HsLit GhcPs -> RnM ()
forall p. HsLit p -> RnM ()
rnLit HsLit GhcPs
lit); Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XLitPat GhcRn -> HsLit GhcRn -> Pat GhcRn
forall p. XLitPat p -> HsLit p -> Pat p
LitPat XLitPat GhcPs
XLitPat GhcRn
x (HsLit GhcPs -> HsLit GhcRn
forall (p1 :: Pass) (p2 :: Pass).
HsLit (GhcPass p1) -> HsLit (GhcPass p2)
convertLit HsLit GhcPs
lit)) }

rnPatAndThen NameMaker
_ (NPat XNPat GhcPs
x (L SrcAnn NoEpAnns
l HsOverLit GhcPs
lit) Maybe (SyntaxExpr GhcPs)
mb_neg SyntaxExpr GhcPs
_eq)
  = do { (HsOverLit GhcRn
lit', Maybe (HsExpr GhcRn)
mb_neg') <- RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn))
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
 -> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn)))
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn))
forall a b. (a -> b) -> a -> b
$ HsOverLit GhcPs
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
forall t.
(XXOverLit t ~ DataConCantHappen) =>
HsOverLit t
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
rnOverLit HsOverLit GhcPs
lit
       ; Maybe SyntaxExprRn
mb_neg' -- See Note [Negative zero]
           <- let negative :: IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
negative = do { (SyntaxExprRn
neg, FreeVars
fvs) <- Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
negateName
                                ; (Maybe SyntaxExprRn, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (SyntaxExprRn -> Maybe SyntaxExprRn
forall a. a -> Maybe a
Just SyntaxExprRn
neg, FreeVars
fvs) }
                  positive :: IOEnv (Env TcGblEnv TcLclEnv) (Maybe a, FreeVars)
positive = (Maybe a, FreeVars)
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe a, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (Maybe a
forall a. Maybe a
Nothing, FreeVars
emptyFVs)
              in IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
-> CpsRn (Maybe SyntaxExprRn)
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
 -> CpsRn (Maybe SyntaxExprRn))
-> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
-> CpsRn (Maybe SyntaxExprRn)
forall a b. (a -> b) -> a -> b
$ case (Maybe NoExtField
Maybe (SyntaxExpr GhcPs)
mb_neg , Maybe (HsExpr GhcRn)
mb_neg') of
                                  (Maybe NoExtField
Nothing, Just HsExpr GhcRn
_ ) -> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
negative
                                  (Just NoExtField
_ , Maybe (HsExpr GhcRn)
Nothing) -> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
negative
                                  (Maybe NoExtField
Nothing, Maybe (HsExpr GhcRn)
Nothing) -> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall {a}. IOEnv (Env TcGblEnv TcLclEnv) (Maybe a, FreeVars)
positive
                                  (Just NoExtField
_ , Just HsExpr GhcRn
_ ) -> IOEnv (Env TcGblEnv TcLclEnv) (Maybe SyntaxExprRn, FreeVars)
forall {a}. IOEnv (Env TcGblEnv TcLclEnv) (Maybe a, FreeVars)
positive
       ; SyntaxExprRn
eq' <- RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn))
-> RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a b. (a -> b) -> a -> b
$ Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
eqName
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XNPat GhcRn
-> XRec GhcRn (HsOverLit GhcRn)
-> Maybe (SyntaxExpr GhcRn)
-> SyntaxExpr GhcRn
-> Pat GhcRn
forall p.
XNPat p
-> XRec p (HsOverLit p)
-> Maybe (SyntaxExpr p)
-> SyntaxExpr p
-> Pat p
NPat XNPat GhcPs
XNPat GhcRn
x (SrcAnn NoEpAnns
-> HsOverLit GhcRn
-> GenLocated (SrcAnn NoEpAnns) (HsOverLit GhcRn)
forall l e. l -> e -> GenLocated l e
L SrcAnn NoEpAnns
l HsOverLit GhcRn
lit') Maybe (SyntaxExpr GhcRn)
Maybe SyntaxExprRn
mb_neg' SyntaxExpr GhcRn
SyntaxExprRn
eq') }

rnPatAndThen NameMaker
mk (NPlusKPat XNPlusKPat GhcPs
_ XRec GhcPs (IdP GhcPs)
rdr (L SrcAnn NoEpAnns
l HsOverLit GhcPs
lit) HsOverLit GhcPs
_ SyntaxExpr GhcPs
_ SyntaxExpr GhcPs
_ )
  = do { Name
new_name <- NameMaker -> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn Name
newPatName NameMaker
mk (GenLocated (SrcAnn NameAnn) RdrName
-> GenLocated (SrcAnn NameAnn) RdrName
forall a1 a2. LocatedAn a1 a2 -> LocatedN a2
l2n XRec GhcPs (IdP GhcPs)
GenLocated (SrcAnn NameAnn) RdrName
rdr)
       ; (HsOverLit GhcRn
lit', Maybe (HsExpr GhcRn)
_) <- RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn))
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
 -> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn)))
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> CpsRn (HsOverLit GhcRn, Maybe (HsExpr GhcRn))
forall a b. (a -> b) -> a -> b
$ HsOverLit GhcPs
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
forall t.
(XXOverLit t ~ DataConCantHappen) =>
HsOverLit t
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
rnOverLit HsOverLit GhcPs
lit -- See Note [Negative zero]
                                                -- We skip negateName as
                                                -- negative zero doesn't make
                                                -- sense in n + k patterns
       ; SyntaxExprRn
minus <- RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn))
-> RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a b. (a -> b) -> a -> b
$ Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
minusName
       ; SyntaxExprRn
ge    <- RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn))
-> RnM (SyntaxExpr GhcRn, FreeVars) -> CpsRn (SyntaxExpr GhcRn)
forall a b. (a -> b) -> a -> b
$ Name -> RnM (SyntaxExpr GhcRn, FreeVars)
lookupSyntax Name
geName
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XNPlusKPat GhcRn
-> LIdP GhcRn
-> XRec GhcRn (HsOverLit GhcRn)
-> HsOverLit GhcRn
-> SyntaxExpr GhcRn
-> SyntaxExpr GhcRn
-> Pat GhcRn
forall p.
XNPlusKPat p
-> LIdP p
-> XRec p (HsOverLit p)
-> HsOverLit p
-> SyntaxExpr p
-> SyntaxExpr p
-> Pat p
NPlusKPat XNPlusKPat GhcRn
NoExtField
noExtField (SrcAnn NameAnn -> Name -> LocatedN Name
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcAnn NameAnn
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan (SrcSpan -> SrcAnn NameAnn) -> SrcSpan -> SrcAnn NameAnn
forall a b. (a -> b) -> a -> b
$ Name -> SrcSpan
nameSrcSpan Name
new_name) Name
new_name)
                                      (SrcAnn NoEpAnns
-> HsOverLit GhcRn
-> GenLocated (SrcAnn NoEpAnns) (HsOverLit GhcRn)
forall l e. l -> e -> GenLocated l e
L SrcAnn NoEpAnns
l HsOverLit GhcRn
lit') HsOverLit GhcRn
lit' SyntaxExpr GhcRn
SyntaxExprRn
ge SyntaxExpr GhcRn
SyntaxExprRn
minus) }
                -- The Report says that n+k patterns must be in Integral

rnPatAndThen NameMaker
mk (AsPat XAsPat GhcPs
_ XRec GhcPs (IdP GhcPs)
rdr LHsToken "@" GhcPs
at LPat GhcPs
pat)
  = do { LocatedN Name
new_name <- NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
newPatLName NameMaker
mk XRec GhcPs (IdP GhcPs)
GenLocated (SrcAnn NameAnn) RdrName
rdr
       ; GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XAsPat GhcRn
-> LIdP GhcRn -> LHsToken "@" GhcRn -> LPat GhcRn -> Pat GhcRn
forall p. XAsPat p -> LIdP p -> LHsToken "@" p -> LPat p -> Pat p
AsPat XAsPat GhcRn
NoExtField
noExtField LIdP GhcRn
LocatedN Name
new_name LHsToken "@" GhcPs
LHsToken "@" GhcRn
at LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat') }

rnPatAndThen NameMaker
mk p :: Pat GhcPs
p@(ViewPat XViewPat GhcPs
_ LHsExpr GhcPs
expr LPat GhcPs
pat)
  = do { RnM () -> CpsRn ()
forall a. RnM a -> CpsRn a
liftCps (RnM () -> CpsRn ()) -> RnM () -> CpsRn ()
forall a b. (a -> b) -> a -> b
$ do { Bool
vp_flag <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.ViewPatterns
                      ; Bool -> TcRnMessage -> RnM ()
checkErr Bool
vp_flag (Pat GhcPs -> TcRnMessage
TcRnIllegalViewPattern Pat GhcPs
p) }
         -- Because of the way we're arranging the recursive calls,
         -- this will be in the right context
       ; GenLocated SrcSpanAnnA (HsExpr GhcRn)
expr' <- RnM (LHsExpr GhcRn, FreeVars) -> CpsRn (LHsExpr GhcRn)
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM (LHsExpr GhcRn, FreeVars) -> CpsRn (LHsExpr GhcRn))
-> RnM (LHsExpr GhcRn, FreeVars) -> CpsRn (LHsExpr GhcRn)
forall a b. (a -> b) -> a -> b
$ LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
expr
       ; GenLocated SrcSpanAnnA (Pat GhcRn)
pat' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
       -- Note: at this point the PreTcType in ty can only be a placeHolder
       -- ; return (ViewPat expr' pat' ty) }

       -- Note: we can't cook up an inverse for an arbitrary view pattern,
       -- so we pass 'Nothing'.
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XViewPat GhcRn -> LHsExpr GhcRn -> LPat GhcRn -> Pat GhcRn
forall p. XViewPat p -> LHsExpr p -> LPat p -> Pat p
ViewPat Maybe (HsExpr GhcRn)
XViewPat GhcRn
forall a. Maybe a
Nothing LHsExpr GhcRn
GenLocated SrcSpanAnnA (HsExpr GhcRn)
expr' LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat') }

rnPatAndThen NameMaker
mk (ConPat XConPat GhcPs
_ XRec GhcPs (ConLikeP GhcPs)
con HsConPatDetails GhcPs
args)
   -- rnConPatAndThen takes care of reconstructing the pattern
   -- The pattern for the empty list needs to be replaced by an empty explicit list pattern when overloaded lists is turned on.
  = case GenLocated (SrcAnn NameAnn) RdrName -> RdrName
forall l e. GenLocated l e -> e
unLoc XRec GhcPs (ConLikeP GhcPs)
GenLocated (SrcAnn NameAnn) RdrName
con RdrName -> RdrName -> Bool
forall a. Eq a => a -> a -> Bool
== Name -> RdrName
nameRdrName (DataCon -> Name
dataConName DataCon
nilDataCon) of
      Bool
True    -> do { Bool
ol_flag <- RnM Bool -> CpsRn Bool
forall a. RnM a -> CpsRn a
liftCps (RnM Bool -> CpsRn Bool) -> RnM Bool -> CpsRn Bool
forall a b. (a -> b) -> a -> b
$ Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedLists
                    ; if Bool
ol_flag then NameMaker -> Pat GhcPs -> CpsRn (Pat GhcRn)
rnPatAndThen NameMaker
mk (XListPat GhcPs -> [LPat GhcPs] -> Pat GhcPs
forall p. XListPat p -> [LPat p] -> Pat p
ListPat XListPat GhcPs
EpAnn AnnList
forall a. EpAnn a
noAnn [])
                                 else NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName
-> HsConPatDetails GhcPs
-> CpsRn (Pat GhcRn)
rnConPatAndThen NameMaker
mk XRec GhcPs (ConLikeP GhcPs)
GenLocated (SrcAnn NameAnn) RdrName
con HsConPatDetails GhcPs
args}
      Bool
False   -> NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName
-> HsConPatDetails GhcPs
-> CpsRn (Pat GhcRn)
rnConPatAndThen NameMaker
mk XRec GhcPs (ConLikeP GhcPs)
GenLocated (SrcAnn NameAnn) RdrName
con HsConPatDetails GhcPs
args

rnPatAndThen NameMaker
mk (ListPat XListPat GhcPs
_ [LPat GhcPs]
pats)
  = do { Bool
opt_OverloadedLists  <- RnM Bool -> CpsRn Bool
forall a. RnM a -> CpsRn a
liftCps (RnM Bool -> CpsRn Bool) -> RnM Bool -> CpsRn Bool
forall a b. (a -> b) -> a -> b
$ Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.OverloadedLists
       ; [GenLocated SrcSpanAnnA (Pat GhcRn)]
pats' <- NameMaker -> [LPat GhcPs] -> CpsRn [LPat GhcRn]
forall (f :: * -> *).
Traversable f =>
NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen NameMaker
mk [LPat GhcPs]
pats
       ; if Bool -> Bool
not Bool
opt_OverloadedLists
         then Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XListPat GhcRn -> [LPat GhcRn] -> Pat GhcRn
forall p. XListPat p -> [LPat p] -> Pat p
ListPat XListPat GhcRn
NoExtField
noExtField [LPat GhcRn]
[GenLocated SrcSpanAnnA (Pat GhcRn)]
pats')
         else
    -- If OverloadedLists is enabled, desugar to a view pattern.
    -- See Note [Desugaring overloaded list patterns]
    do { (Name
to_list_name,FreeVars
_)     <- RnM (Name, FreeVars) -> CpsRn (Name, FreeVars)
forall a. RnM a -> CpsRn a
liftCps (RnM (Name, FreeVars) -> CpsRn (Name, FreeVars))
-> RnM (Name, FreeVars) -> CpsRn (Name, FreeVars)
forall a b. (a -> b) -> a -> b
$ Name -> RnM (Name, FreeVars)
lookupSyntaxName Name
toListName
       -- Use 'fromList' as proof of invertibility of the view pattern.
       -- See Note [Invertible view patterns] in GHC.Tc.TyCl.PatSyn
       ; (Name
from_list_n_name,FreeVars
_) <- RnM (Name, FreeVars) -> CpsRn (Name, FreeVars)
forall a. RnM a -> CpsRn a
liftCps (RnM (Name, FreeVars) -> CpsRn (Name, FreeVars))
-> RnM (Name, FreeVars) -> CpsRn (Name, FreeVars)
forall a b. (a -> b) -> a -> b
$ Name -> RnM (Name, FreeVars)
lookupSyntaxName Name
fromListNName
       ; let
           lit_n :: IntegralLit
lit_n   = Int -> IntegralLit
forall a. Integral a => a -> IntegralLit
mkIntegralLit ([GenLocated SrcSpanAnnA (Pat GhcPs)] -> Int
forall a. [a] -> Int
forall (t :: * -> *) a. Foldable t => t a -> Int
length [LPat GhcPs]
[GenLocated SrcSpanAnnA (Pat GhcPs)]
pats)
           hs_lit :: GenLocated SrcSpanAnnA (HsExpr GhcRn)
hs_lit  = IntegralLit -> GenLocated SrcSpanAnnA (HsExpr GhcRn)
forall an. IntegralLit -> LocatedAn an (HsExpr GhcRn)
genHsIntegralLit IntegralLit
lit_n
           inverse :: HsExpr GhcRn
inverse = Name -> [LHsExpr GhcRn] -> HsExpr GhcRn
genHsApps Name
from_list_n_name [LHsExpr GhcRn
GenLocated SrcSpanAnnA (HsExpr GhcRn)
hs_lit]
           rn_list_pat :: Pat GhcRn
rn_list_pat  = XListPat GhcRn -> [LPat GhcRn] -> Pat GhcRn
forall p. XListPat p -> [LPat p] -> Pat p
ListPat XListPat GhcRn
NoExtField
noExtField [LPat GhcRn]
[GenLocated SrcSpanAnnA (Pat GhcRn)]
pats'
           exp_expr :: LHsExpr GhcRn
exp_expr     = Name -> LHsExpr GhcRn
genLHsVar Name
to_list_name
           exp_list_pat :: Pat GhcRn
exp_list_pat = XViewPat GhcRn -> LHsExpr GhcRn -> LPat GhcRn -> Pat GhcRn
forall p. XViewPat p -> LHsExpr p -> LPat p -> Pat p
ViewPat (HsExpr GhcRn -> Maybe (HsExpr GhcRn)
forall a. a -> Maybe a
Just HsExpr GhcRn
inverse) LHsExpr GhcRn
exp_expr (Pat GhcRn -> GenLocated SrcSpanAnnA (Pat GhcRn)
forall a an. a -> LocatedAn an a
wrapGenSpan Pat GhcRn
rn_list_pat)
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (Pat GhcRn -> CpsRn (Pat GhcRn)) -> Pat GhcRn -> CpsRn (Pat GhcRn)
forall a b. (a -> b) -> a -> b
$ Pat GhcRn -> Pat GhcRn -> Pat GhcRn
mkExpandedPat Pat GhcRn
rn_list_pat Pat GhcRn
exp_list_pat }}

rnPatAndThen NameMaker
mk (TuplePat XTuplePat GhcPs
_ [LPat GhcPs]
pats Boxity
boxed)
  = do { [GenLocated SrcSpanAnnA (Pat GhcRn)]
pats' <- NameMaker -> [LPat GhcPs] -> CpsRn [LPat GhcRn]
forall (f :: * -> *).
Traversable f =>
NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen NameMaker
mk [LPat GhcPs]
pats
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XTuplePat GhcRn -> [LPat GhcRn] -> Boxity -> Pat GhcRn
forall p. XTuplePat p -> [LPat p] -> Boxity -> Pat p
TuplePat XTuplePat GhcRn
NoExtField
noExtField [LPat GhcRn]
[GenLocated SrcSpanAnnA (Pat GhcRn)]
pats' Boxity
boxed) }

rnPatAndThen NameMaker
mk (SumPat XSumPat GhcPs
_ LPat GhcPs
pat Int
alt Int
arity)
  = do { GenLocated SrcSpanAnnA (Pat GhcRn)
pat <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat
       ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XSumPat GhcRn -> LPat GhcRn -> Int -> Int -> Pat GhcRn
forall p. XSumPat p -> LPat p -> Int -> Int -> Pat p
SumPat XSumPat GhcRn
NoExtField
noExtField LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat Int
alt Int
arity)
       }

rnPatAndThen NameMaker
mk (SplicePat XSplicePat GhcPs
_ HsUntypedSplice GhcPs
splice)
  = do { (HsUntypedSplice GhcRn,
 HsUntypedSpliceResult (GenLocated SrcSpanAnnA (Pat GhcPs)))
eith <- RnM
  ((HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs)),
   FreeVars)
-> CpsRn
     (HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs))
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM
   ((HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs)),
    FreeVars)
 -> CpsRn
      (HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs)))
-> RnM
     ((HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs)),
      FreeVars)
-> CpsRn
     (HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs))
forall a b. (a -> b) -> a -> b
$ HsUntypedSplice GhcPs
-> RnM
     ((HsUntypedSplice GhcRn, HsUntypedSpliceResult (LPat GhcPs)),
      FreeVars)
rnSplicePat HsUntypedSplice GhcPs
splice
       ; case (HsUntypedSplice GhcRn,
 HsUntypedSpliceResult (GenLocated SrcSpanAnnA (Pat GhcPs)))
eith of   -- See Note [rnSplicePat] in GHC.Rename.Splice
           (HsUntypedSplice GhcRn
rn_splice, HsUntypedSpliceTop ThModFinalizers
mfs GenLocated SrcSpanAnnA (Pat GhcPs)
pat) -> -- Splice was top-level and thus run, creating Pat GhcPs
               LPat GhcRn -> Pat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn) -> Pat GhcRn
forall (pass :: Pass). LPat (GhcPass pass) -> Pat (GhcPass pass)
gParPat (GenLocated SrcSpanAnnA (Pat GhcRn) -> Pat GhcRn)
-> (GenLocated SrcSpanAnnA (Pat GhcRn)
    -> GenLocated SrcSpanAnnA (Pat GhcRn))
-> GenLocated SrcSpanAnnA (Pat GhcRn)
-> Pat GhcRn
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ((Pat GhcRn -> Pat GhcRn)
-> GenLocated SrcSpanAnnA (Pat GhcRn)
-> GenLocated SrcSpanAnnA (Pat GhcRn)
forall a b.
(a -> b) -> GenLocated SrcSpanAnnA a -> GenLocated SrcSpanAnnA b
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap ((HsUntypedSpliceResult (Pat GhcRn)
 -> HsUntypedSplice GhcRn -> Pat GhcRn)
-> HsUntypedSplice GhcRn
-> HsUntypedSpliceResult (Pat GhcRn)
-> Pat GhcRn
forall a b c. (a -> b -> c) -> b -> a -> c
flip XSplicePat GhcRn -> HsUntypedSplice GhcRn -> Pat GhcRn
HsUntypedSpliceResult (Pat GhcRn)
-> HsUntypedSplice GhcRn -> Pat GhcRn
forall p. XSplicePat p -> HsUntypedSplice p -> Pat p
SplicePat HsUntypedSplice GhcRn
rn_splice (HsUntypedSpliceResult (Pat GhcRn) -> Pat GhcRn)
-> (Pat GhcRn -> HsUntypedSpliceResult (Pat GhcRn))
-> Pat GhcRn
-> Pat GhcRn
forall b c a. (b -> c) -> (a -> b) -> a -> c
. ThModFinalizers -> Pat GhcRn -> HsUntypedSpliceResult (Pat GhcRn)
forall thing.
ThModFinalizers -> thing -> HsUntypedSpliceResult thing
HsUntypedSpliceTop ThModFinalizers
mfs)) (GenLocated SrcSpanAnnA (Pat GhcRn) -> Pat GhcRn)
-> CpsRn (GenLocated SrcSpanAnnA (Pat GhcRn)) -> CpsRn (Pat GhcRn)
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
GenLocated SrcSpanAnnA (Pat GhcPs)
pat
           (HsUntypedSplice GhcRn
rn_splice, HsUntypedSpliceNested Name
splice_name) -> Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (XSplicePat GhcRn -> HsUntypedSplice GhcRn -> Pat GhcRn
forall p. XSplicePat p -> HsUntypedSplice p -> Pat p
SplicePat (Name -> HsUntypedSpliceResult (Pat GhcRn)
forall thing. Name -> HsUntypedSpliceResult thing
HsUntypedSpliceNested Name
splice_name) HsUntypedSplice GhcRn
rn_splice) -- Splice was nested and thus already renamed
       }

--------------------
rnConPatAndThen :: NameMaker
                -> LocatedN RdrName    -- the constructor
                -> HsConPatDetails GhcPs
                -> CpsRn (Pat GhcRn)

rnConPatAndThen :: NameMaker
-> GenLocated (SrcAnn NameAnn) RdrName
-> HsConPatDetails GhcPs
-> CpsRn (Pat GhcRn)
rnConPatAndThen NameMaker
mk GenLocated (SrcAnn NameAnn) RdrName
con (PrefixCon [HsConPatTyArg (NoGhcTc GhcPs)]
tyargs [LPat GhcPs]
pats)
  = do  { LocatedN Name
con' <- GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
lookupConCps GenLocated (SrcAnn NameAnn) RdrName
con
        ; RnM () -> CpsRn ()
forall a. RnM a -> CpsRn a
liftCps RnM ()
check_lang_exts
        ; [HsConPatTyArg GhcRn]
tyargs' <- (HsConPatTyArg GhcPs -> CpsRn (HsConPatTyArg GhcRn))
-> [HsConPatTyArg GhcPs] -> CpsRn [HsConPatTyArg GhcRn]
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
forall (m :: * -> *) a b. Monad m => (a -> m b) -> [a] -> m [b]
mapM HsConPatTyArg GhcPs -> CpsRn (HsConPatTyArg GhcRn)
rnConPatTyArg [HsConPatTyArg (NoGhcTc GhcPs)]
[HsConPatTyArg GhcPs]
tyargs
        ; [GenLocated SrcSpanAnnA (Pat GhcRn)]
pats' <- NameMaker -> [LPat GhcPs] -> CpsRn [LPat GhcRn]
forall (f :: * -> *).
Traversable f =>
NameMaker -> f (LPat GhcPs) -> CpsRn (f (LPat GhcRn))
rnLPatsAndThen NameMaker
mk [LPat GhcPs]
pats
        ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (Pat GhcRn -> CpsRn (Pat GhcRn)) -> Pat GhcRn -> CpsRn (Pat GhcRn)
forall a b. (a -> b) -> a -> b
$ ConPat
            { pat_con_ext :: XConPat GhcRn
pat_con_ext = XConPat GhcRn
NoExtField
noExtField
            , pat_con :: XRec GhcRn (ConLikeP GhcRn)
pat_con = XRec GhcRn (ConLikeP GhcRn)
LocatedN Name
con'
            , pat_args :: HsConPatDetails GhcRn
pat_args = [HsConPatTyArg GhcRn]
-> [GenLocated SrcSpanAnnA (Pat GhcRn)]
-> HsConDetails
     (HsConPatTyArg GhcRn)
     (GenLocated SrcSpanAnnA (Pat GhcRn))
     (HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn)))
forall tyarg arg rec.
[tyarg] -> [arg] -> HsConDetails tyarg arg rec
PrefixCon [HsConPatTyArg GhcRn]
tyargs' [GenLocated SrcSpanAnnA (Pat GhcRn)]
pats'
            }
        }
  where
    check_lang_exts :: RnM ()
    check_lang_exts :: RnM ()
check_lang_exts =
      Maybe (HsConPatTyArg GhcPs)
-> (HsConPatTyArg GhcPs -> RnM ()) -> RnM ()
forall (t :: * -> *) (f :: * -> *) a b.
(Foldable t, Applicative f) =>
t a -> (a -> f b) -> f ()
for_ ([HsConPatTyArg GhcPs] -> Maybe (HsConPatTyArg GhcPs)
forall a. [a] -> Maybe a
listToMaybe [HsConPatTyArg (NoGhcTc GhcPs)]
[HsConPatTyArg GhcPs]
tyargs) ((HsConPatTyArg GhcPs -> RnM ()) -> RnM ())
-> (HsConPatTyArg GhcPs -> RnM ()) -> RnM ()
forall a b. (a -> b) -> a -> b
$ \ HsConPatTyArg GhcPs
arg ->
        do { Bool
type_abs   <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.TypeAbstractions
           ; Bool
type_app   <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.TypeApplications
           ; Bool
scoped_tvs <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.ScopedTypeVariables
           ; if | Bool
type_abs
                -> () -> RnM ()
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ()

                -- As per [GHC Proposal 604](https://github.com/ghc-proposals/ghc-proposals/pull/604/),
                -- we allow type applications in constructor patterns when -XTypeApplications and
                -- -XScopedTypeVariables are both enabled, but we emit a warning when doing so.
                --
                -- This warning is scheduled to become an error in GHC 9.12, in
                -- which case we will get the usual error (below),
                -- which suggests enabling -XTypeAbstractions.
                | Bool
type_app Bool -> Bool -> Bool
&& Bool
scoped_tvs
                -> TcRnMessage -> RnM ()
addDiagnostic TcRnMessage
TcRnDeprecatedInvisTyArgInConPat

                | Bool
otherwise
                -> TcRnMessage -> RnM ()
addErrTc (TcRnMessage -> RnM ()) -> TcRnMessage -> RnM ()
forall a b. (a -> b) -> a -> b
$ TypeApplication -> TcRnMessage
TcRnTypeApplicationsDisabled (HsConPatTyArg GhcPs -> TypeApplication
TypeApplicationInPattern HsConPatTyArg GhcPs
arg)
           }

    rnConPatTyArg :: HsConPatTyArg GhcPs -> CpsRn (HsConPatTyArg GhcRn)
rnConPatTyArg (HsConPatTyArg LHsToken "@" GhcPs
at HsPatSigType GhcPs
t) = do
      HsPatSigType GhcRn
t' <- (forall r.
 (HsPatSigType GhcRn -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn (HsPatSigType GhcRn)
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
liftCpsWithCont ((forall r.
  (HsPatSigType GhcRn -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
 -> CpsRn (HsPatSigType GhcRn))
-> (forall r.
    (HsPatSigType GhcRn -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn (HsPatSigType GhcRn)
forall a b. (a -> b) -> a -> b
$ HsDocContext
-> HsPatSigType GhcPs
-> (HsPatSigType GhcRn
    -> IOEnv (Env TcGblEnv TcLclEnv) (r, FreeVars))
-> IOEnv (Env TcGblEnv TcLclEnv) (r, FreeVars)
forall r.
HsDocContext
-> HsPatSigType GhcPs
-> (HsPatSigType GhcRn -> RnM (r, FreeVars))
-> RnM (r, FreeVars)
rnHsPatSigTypeBindingVars HsDocContext
HsTypeCtx HsPatSigType GhcPs
t
      HsConPatTyArg GhcRn -> CpsRn (HsConPatTyArg GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsToken "@" GhcRn -> HsPatSigType GhcRn -> HsConPatTyArg GhcRn
forall p. LHsToken "@" p -> HsPatSigType p -> HsConPatTyArg p
HsConPatTyArg LHsToken "@" GhcPs
LHsToken "@" GhcRn
at HsPatSigType GhcRn
t')

rnConPatAndThen NameMaker
mk GenLocated (SrcAnn NameAnn) RdrName
con (InfixCon LPat GhcPs
pat1 LPat GhcPs
pat2)
  = do  { LocatedN Name
con' <- GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
lookupConCps GenLocated (SrcAnn NameAnn) RdrName
con
        ; GenLocated SrcSpanAnnA (Pat GhcRn)
pat1' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat1
        ; GenLocated SrcSpanAnnA (Pat GhcRn)
pat2' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen NameMaker
mk LPat GhcPs
pat2
        ; Fixity
fixity <- RnM Fixity -> CpsRn Fixity
forall a. RnM a -> CpsRn a
liftCps (RnM Fixity -> CpsRn Fixity) -> RnM Fixity -> CpsRn Fixity
forall a b. (a -> b) -> a -> b
$ Name -> RnM Fixity
lookupFixityRn (LocatedN Name -> Name
forall l e. GenLocated l e -> e
unLoc LocatedN Name
con')
        ; RnM (Pat GhcRn) -> CpsRn (Pat GhcRn)
forall a. RnM a -> CpsRn a
liftCps (RnM (Pat GhcRn) -> CpsRn (Pat GhcRn))
-> RnM (Pat GhcRn) -> CpsRn (Pat GhcRn)
forall a b. (a -> b) -> a -> b
$ LocatedN Name
-> Fixity -> LPat GhcRn -> LPat GhcRn -> RnM (Pat GhcRn)
mkConOpPatRn LocatedN Name
con' Fixity
fixity LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat1' LPat GhcRn
GenLocated SrcSpanAnnA (Pat GhcRn)
pat2' }

rnConPatAndThen NameMaker
mk GenLocated (SrcAnn NameAnn) RdrName
con (RecCon HsRecFields GhcPs (LPat GhcPs)
rpats)
  = do  { LocatedN Name
con' <- GenLocated (SrcAnn NameAnn) RdrName -> CpsRn (LocatedN Name)
lookupConCps GenLocated (SrcAnn NameAnn) RdrName
con
        ; HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))
rpats' <- NameMaker
-> LocatedN Name
-> HsRecFields GhcPs (LPat GhcPs)
-> CpsRn (HsRecFields GhcRn (LPat GhcRn))
rnHsRecPatsAndThen NameMaker
mk LocatedN Name
con' HsRecFields GhcPs (LPat GhcPs)
rpats
        ; Pat GhcRn -> CpsRn (Pat GhcRn)
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (Pat GhcRn -> CpsRn (Pat GhcRn)) -> Pat GhcRn -> CpsRn (Pat GhcRn)
forall a b. (a -> b) -> a -> b
$ ConPat
            { pat_con_ext :: XConPat GhcRn
pat_con_ext = XConPat GhcRn
NoExtField
noExtField
            , pat_con :: XRec GhcRn (ConLikeP GhcRn)
pat_con = XRec GhcRn (ConLikeP GhcRn)
LocatedN Name
con'
            , pat_args :: HsConPatDetails GhcRn
pat_args = HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))
-> HsConDetails
     (HsConPatTyArg GhcRn)
     (GenLocated SrcSpanAnnA (Pat GhcRn))
     (HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn)))
forall tyarg arg rec. rec -> HsConDetails tyarg arg rec
RecCon HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))
rpats'
            }
        }

checkUnusedRecordWildcardCps :: SrcSpan -> Maybe [Name] -> CpsRn ()
checkUnusedRecordWildcardCps :: SrcSpan -> Maybe [Name] -> CpsRn ()
checkUnusedRecordWildcardCps SrcSpan
loc Maybe [Name]
dotdot_names =
  (forall r. (() -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn ()
forall b.
(forall r. (b -> RnM (r, FreeVars)) -> RnM (r, FreeVars))
-> CpsRn b
CpsRn (\() -> RnM (r, FreeVars)
thing -> do
                    (r
r, FreeVars
fvs) <- () -> RnM (r, FreeVars)
thing ()
                    SrcSpan -> FreeVars -> Maybe [Name] -> RnM ()
checkUnusedRecordWildcard SrcSpan
loc FreeVars
fvs Maybe [Name]
dotdot_names
                    (r, FreeVars) -> RnM (r, FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (r
r, FreeVars
fvs) )
--------------------
rnHsRecPatsAndThen :: NameMaker
                   -> LocatedN Name      -- Constructor
                   -> HsRecFields GhcPs (LPat GhcPs)
                   -> CpsRn (HsRecFields GhcRn (LPat GhcRn))
rnHsRecPatsAndThen :: NameMaker
-> LocatedN Name
-> HsRecFields GhcPs (LPat GhcPs)
-> CpsRn (HsRecFields GhcRn (LPat GhcRn))
rnHsRecPatsAndThen NameMaker
mk (L SrcAnn NameAnn
_ Name
con)
     hs_rec_fields :: HsRecFields GhcPs (LPat GhcPs)
hs_rec_fields@(HsRecFields { rec_dotdot :: forall p arg. HsRecFields p arg -> Maybe (XRec p RecFieldsDotDot)
rec_dotdot = Maybe (XRec GhcPs RecFieldsDotDot)
dd })
  = do { [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcPs)))]
flds <- RnM
  ([GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
         (GenLocated SrcSpanAnnA (Pat GhcPs)))],
   FreeVars)
-> CpsRn
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcPs)))]
forall a. RnM (a, FreeVars) -> CpsRn a
liftCpsFV (RnM
   ([GenLocated
       SrcSpanAnnA
       (HsFieldBind
          (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
          (GenLocated SrcSpanAnnA (Pat GhcPs)))],
    FreeVars)
 -> CpsRn
      [GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (Pat GhcPs)))])
-> RnM
     ([GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (Pat GhcPs)))],
      FreeVars)
-> CpsRn
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcPs)))]
forall a b. (a -> b) -> a -> b
$ HsRecFieldContext
-> (SrcSpan -> RdrName -> Pat GhcPs)
-> HsRecFields GhcPs (GenLocated SrcSpanAnnA (Pat GhcPs))
-> RnM
     ([LHsRecField GhcRn (GenLocated SrcSpanAnnA (Pat GhcPs))],
      FreeVars)
forall arg.
HsRecFieldContext
-> (SrcSpan -> RdrName -> arg)
-> HsRecFields GhcPs (LocatedA arg)
-> RnM ([LHsRecField GhcRn (LocatedA arg)], FreeVars)
rnHsRecFields (Name -> HsRecFieldContext
HsRecFieldPat Name
con) SrcSpan -> IdP GhcPs -> Pat GhcPs
SrcSpan -> RdrName -> Pat GhcPs
forall {p} {ann}.
(XVarPat p ~ NoExtField,
 XRec p (IdP p) ~ GenLocated (SrcAnn ann) (IdP p)) =>
SrcSpan -> IdP p -> Pat p
mkVarPat
                                            HsRecFields GhcPs (LPat GhcPs)
HsRecFields GhcPs (GenLocated SrcSpanAnnA (Pat GhcPs))
hs_rec_fields
       ; [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcRn)))]
flds' <- ((GenLocated
    SrcSpanAnnA
    (HsFieldBind
       (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
       (GenLocated SrcSpanAnnA (Pat GhcPs))),
  Int)
 -> CpsRn
      (GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (Pat GhcRn)))))
-> [(GenLocated
       SrcSpanAnnA
       (HsFieldBind
          (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
          (GenLocated SrcSpanAnnA (Pat GhcPs))),
     Int)]
-> CpsRn
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcRn)))]
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
forall (m :: * -> *) a b. Monad m => (a -> m b) -> [a] -> m [b]
mapM (GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcPs))),
 Int)
-> CpsRn
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcRn))))
rn_field ([GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcPs)))]
flds [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcPs)))]
-> [Int]
-> [(GenLocated
       SrcSpanAnnA
       (HsFieldBind
          (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
          (GenLocated SrcSpanAnnA (Pat GhcPs))),
     Int)]
forall a b. [a] -> [b] -> [(a, b)]
`zip` [Int
1..])
       ; Maybe [Name] -> CpsRn ()
check_unused_wildcard ([GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LPat GhcRn))]
-> GenLocated SrcSpan RecFieldsDotDot -> [IdP GhcRn]
forall {p} {l} {lhs} {l}.
CollectPass p =>
[GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
-> GenLocated l RecFieldsDotDot -> [IdP p]
implicit_binders [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LPat GhcRn))]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcRn)))]
flds' (GenLocated SrcSpan RecFieldsDotDot -> [Name])
-> Maybe (GenLocated SrcSpan RecFieldsDotDot) -> Maybe [Name]
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Maybe (XRec GhcPs RecFieldsDotDot)
Maybe (GenLocated SrcSpan RecFieldsDotDot)
dd)
       ; HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))
-> CpsRn (HsRecFields GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn)))
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (HsRecFields { rec_flds :: [LHsRecField GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))]
rec_flds = [LHsRecField GhcRn (GenLocated SrcSpanAnnA (Pat GhcRn))]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcRn)))]
flds', rec_dotdot :: Maybe (XRec GhcRn RecFieldsDotDot)
rec_dotdot = Maybe (XRec GhcPs RecFieldsDotDot)
Maybe (XRec GhcRn RecFieldsDotDot)
dd }) }
  where
    mkVarPat :: SrcSpan -> IdP p -> Pat p
mkVarPat SrcSpan
l IdP p
n = XVarPat p -> XRec p (IdP p) -> Pat p
forall p. XVarPat p -> LIdP p -> Pat p
VarPat XVarPat p
NoExtField
noExtField (SrcAnn ann -> IdP p -> GenLocated (SrcAnn ann) (IdP p)
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcAnn ann
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
l) IdP p
n)
    rn_field :: (GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (Pat GhcPs))),
 Int)
-> CpsRn
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcRn))))
rn_field (L SrcSpanAnnA
l HsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
  (GenLocated SrcSpanAnnA (Pat GhcPs))
fld, Int
n') =
      do { GenLocated SrcSpanAnnA (Pat GhcRn)
arg' <- NameMaker -> LPat GhcPs -> CpsRn (LPat GhcRn)
rnLPatAndThen (Maybe (GenLocated SrcSpan RecFieldsDotDot)
-> NameMaker -> RecFieldsDotDot -> NameMaker
forall {a} {l}.
Ord a =>
Maybe (GenLocated l a) -> NameMaker -> a -> NameMaker
nested_mk Maybe (XRec GhcPs RecFieldsDotDot)
Maybe (GenLocated SrcSpan RecFieldsDotDot)
dd NameMaker
mk (Int -> RecFieldsDotDot
RecFieldsDotDot Int
n')) (HsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
  (GenLocated SrcSpanAnnA (Pat GhcPs))
-> GenLocated SrcSpanAnnA (Pat GhcPs)
forall lhs rhs. HsFieldBind lhs rhs -> rhs
hfbRHS HsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
  (GenLocated SrcSpanAnnA (Pat GhcPs))
fld)
         ; GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
     (GenLocated SrcSpanAnnA (Pat GhcRn)))
-> CpsRn
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
           (GenLocated SrcSpanAnnA (Pat GhcRn))))
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return (SrcSpanAnnA
-> HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
     (GenLocated SrcSpanAnnA (Pat GhcRn))
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
        (GenLocated SrcSpanAnnA (Pat GhcRn)))
forall l e. l -> e -> GenLocated l e
L SrcSpanAnnA
l (HsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
  (GenLocated SrcSpanAnnA (Pat GhcPs))
fld { hfbRHS = arg' })) }

    loc :: SrcSpan
loc = SrcSpan
-> (GenLocated SrcSpan RecFieldsDotDot -> SrcSpan)
-> Maybe (GenLocated SrcSpan RecFieldsDotDot)
-> SrcSpan
forall b a. b -> (a -> b) -> Maybe a -> b
maybe SrcSpan
noSrcSpan GenLocated SrcSpan RecFieldsDotDot -> SrcSpan
forall l e. GenLocated l e -> l
getLoc Maybe (XRec GhcPs RecFieldsDotDot)
Maybe (GenLocated SrcSpan RecFieldsDotDot)
dd

    -- Get the arguments of the implicit binders
    implicit_binders :: [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
-> GenLocated l RecFieldsDotDot -> [IdP p]
implicit_binders [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
fs (GenLocated l RecFieldsDotDot -> RecFieldsDotDot
forall l e. GenLocated l e -> e
unLoc -> RecFieldsDotDot Int
n) = CollectFlag p -> [XRec p (Pat p)] -> [IdP p]
forall p. CollectPass p => CollectFlag p -> [LPat p] -> [IdP p]
collectPatsBinders CollectFlag p
forall p. CollectFlag p
CollNoDictBinders [XRec p (Pat p)]
implicit_pats
      where
        implicit_pats :: [XRec p (Pat p)]
implicit_pats = (GenLocated l (HsFieldBind lhs (XRec p (Pat p))) -> XRec p (Pat p))
-> [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
-> [XRec p (Pat p)]
forall a b. (a -> b) -> [a] -> [b]
map (HsFieldBind lhs (XRec p (Pat p)) -> XRec p (Pat p)
forall lhs rhs. HsFieldBind lhs rhs -> rhs
hfbRHS (HsFieldBind lhs (XRec p (Pat p)) -> XRec p (Pat p))
-> (GenLocated l (HsFieldBind lhs (XRec p (Pat p)))
    -> HsFieldBind lhs (XRec p (Pat p)))
-> GenLocated l (HsFieldBind lhs (XRec p (Pat p)))
-> XRec p (Pat p)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. GenLocated l (HsFieldBind lhs (XRec p (Pat p)))
-> HsFieldBind lhs (XRec p (Pat p))
forall l e. GenLocated l e -> e
unLoc) (Int
-> [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
-> [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
forall a. Int -> [a] -> [a]
drop Int
n [GenLocated l (HsFieldBind lhs (XRec p (Pat p)))]
fs)

    -- Don't warn for let P{..} = ... in ...
    check_unused_wildcard :: Maybe [Name] -> CpsRn ()
check_unused_wildcard = case NameMaker
mk of
                              LetMk{} -> CpsRn () -> Maybe [Name] -> CpsRn ()
forall a b. a -> b -> a
const (() -> CpsRn ()
forall a. a -> CpsRn a
forall (m :: * -> *) a. Monad m => a -> m a
return ())
                              LamMk{} -> SrcSpan -> Maybe [Name] -> CpsRn ()
checkUnusedRecordWildcardCps SrcSpan
loc

        -- Suppress unused-match reporting for fields introduced by ".."
    nested_mk :: Maybe (GenLocated l a) -> NameMaker -> a -> NameMaker
nested_mk Maybe (GenLocated l a)
Nothing  NameMaker
mk                    a
_  = NameMaker
mk
    nested_mk (Just GenLocated l a
_) mk :: NameMaker
mk@(LetMk {})         a
_  = NameMaker
mk
    nested_mk (Just (GenLocated l a -> a
forall l e. GenLocated l e -> e
unLoc -> a
n)) (LamMk Bool
report_unused) a
n'
      = Bool -> NameMaker
LamMk (Bool
report_unused Bool -> Bool -> Bool
&& (a
n' a -> a -> Bool
forall a. Ord a => a -> a -> Bool
<= a
n))


{- *********************************************************************
*                                                                      *
              Generating code for HsPatExpanded
      See Note [Handling overloaded and rebindable constructs]
*                                                                      *
********************************************************************* -}

-- | Build a 'HsPatExpansion' out of an extension constructor,
--   and the two components of the expansion: original and
--   desugared patterns
mkExpandedPat
  :: Pat GhcRn -- ^ source pattern
  -> Pat GhcRn -- ^ expanded pattern
  -> Pat GhcRn -- ^ suitably wrapped 'HsPatExpansion'
mkExpandedPat :: Pat GhcRn -> Pat GhcRn -> Pat GhcRn
mkExpandedPat Pat GhcRn
a Pat GhcRn
b = XXPat GhcRn -> Pat GhcRn
forall p. XXPat p -> Pat p
XPat (Pat GhcRn -> Pat GhcRn -> HsPatExpansion (Pat GhcRn) (Pat GhcRn)
forall a b. a -> b -> HsPatExpansion a b
HsPatExpanded Pat GhcRn
a Pat GhcRn
b)

{-
************************************************************************
*                                                                      *
        Record fields
*                                                                      *
************************************************************************
-}

data HsRecFieldContext
  = HsRecFieldCon Name
  | HsRecFieldPat Name
  | HsRecFieldUpd

rnHsRecFields
    :: forall arg.
       HsRecFieldContext
    -> (SrcSpan -> RdrName -> arg)
         -- When punning, use this to build a new field
    -> HsRecFields GhcPs (LocatedA arg)
    -> RnM ([LHsRecField GhcRn (LocatedA arg)], FreeVars)

-- This surprisingly complicated pass
--   a) looks up the field name (possibly using disambiguation)
--   b) fills in puns and dot-dot stuff
-- When we've finished, we've renamed the LHS, but not the RHS,
-- of each x=e binding
--
-- This is used for record construction and pattern-matching, but not updates.

rnHsRecFields :: forall arg.
HsRecFieldContext
-> (SrcSpan -> RdrName -> arg)
-> HsRecFields GhcPs (LocatedA arg)
-> RnM ([LHsRecField GhcRn (LocatedA arg)], FreeVars)
rnHsRecFields HsRecFieldContext
ctxt SrcSpan -> RdrName -> arg
mk_arg (HsRecFields { rec_flds :: forall p arg. HsRecFields p arg -> [LHsRecField p arg]
rec_flds = [LHsRecField GhcPs (LocatedA arg)]
flds, rec_dotdot :: forall p arg. HsRecFields p arg -> Maybe (XRec p RecFieldsDotDot)
rec_dotdot = Maybe (XRec GhcPs RecFieldsDotDot)
dotdot })
  = do { Bool
pun_ok      <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.NamedFieldPuns
       ; Bool
disambig_ok <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.DisambiguateRecordFields
       ; let parent :: Maybe Name
parent = Bool -> Maybe ()
forall (f :: * -> *). Alternative f => Bool -> f ()
guard Bool
disambig_ok Maybe () -> Maybe Name -> Maybe Name
forall a b. Maybe a -> Maybe b -> Maybe b
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> Maybe Name
mb_con
       ; [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
flds1  <- (GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcPs)) (LocatedA arg))
 -> IOEnv
      (Env TcGblEnv TcLclEnv)
      (GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))))
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcPs)) (LocatedA arg))]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
forall (t :: * -> *) (m :: * -> *) a b.
(Traversable t, Monad m) =>
(a -> m b) -> t a -> m (t b)
forall (m :: * -> *) a b. Monad m => (a -> m b) -> [a] -> m [b]
mapM (Bool
-> Maybe Name
-> LHsRecField GhcPs (LocatedA arg)
-> RnM (LHsRecField GhcRn (LocatedA arg))
rn_fld Bool
pun_ok Maybe Name
parent) [LHsRecField GhcPs (LocatedA arg)]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcPs)) (LocatedA arg))]
flds
       ; (NonEmpty RdrName -> RnM ()) -> [NonEmpty RdrName] -> RnM ()
forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
mapM_ (TcRnMessage -> RnM ()
addErr (TcRnMessage -> RnM ())
-> (NonEmpty RdrName -> TcRnMessage) -> NonEmpty RdrName -> RnM ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. HsRecFieldContext -> NonEmpty RdrName -> TcRnMessage
dupFieldErr HsRecFieldContext
ctxt) [NonEmpty RdrName]
dup_flds
       ; [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
dotdot_flds <- Maybe (GenLocated SrcSpan RecFieldsDotDot)
-> Maybe Name
-> [LHsRecField GhcRn (LocatedA arg)]
-> RnM [LHsRecField GhcRn (LocatedA arg)]
rn_dotdot Maybe (XRec GhcPs RecFieldsDotDot)
Maybe (GenLocated SrcSpan RecFieldsDotDot)
dotdot Maybe Name
mb_con [LHsRecField GhcRn (LocatedA arg)]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
flds1
       ; let all_flds :: [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
all_flds | [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> Bool
forall a. [a] -> Bool
forall (t :: * -> *) a. Foldable t => t a -> Bool
null [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
dotdot_flds = [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
flds1
                      | Bool
otherwise        = [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
flds1 [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
forall a. [a] -> [a] -> [a]
++ [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
dotdot_flds
       ; ([GenLocated
    SrcSpanAnnA
    (HsFieldBind
       (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))],
 FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))],
      FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ([GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
all_flds, [Name] -> FreeVars
mkFVs ([LHsRecField GhcRn (LocatedA arg)] -> [Name]
forall arg. [LHsRecField GhcRn arg] -> [Name]
getFieldIds [LHsRecField GhcRn (LocatedA arg)]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
all_flds)) }
  where
    mb_con :: Maybe Name
mb_con = case HsRecFieldContext
ctxt of
                HsRecFieldCon Name
con  -> Name -> Maybe Name
forall a. a -> Maybe a
Just Name
con
                HsRecFieldPat Name
con  -> Name -> Maybe Name
forall a. a -> Maybe a
Just Name
con
                HsRecFieldContext
HsRecFieldUpd      -> Maybe Name
forall a. Maybe a
Nothing

    rn_fld :: Bool -> Maybe Name -> LHsRecField GhcPs (LocatedA arg)
           -> RnM (LHsRecField GhcRn (LocatedA arg))
    rn_fld :: Bool
-> Maybe Name
-> LHsRecField GhcPs (LocatedA arg)
-> RnM (LHsRecField GhcRn (LocatedA arg))
rn_fld Bool
pun_ok Maybe Name
parent (L SrcSpanAnnA
l
                           (HsFieldBind
                              { hfbLHS :: forall lhs rhs. HsFieldBind lhs rhs -> lhs
hfbLHS = L SrcAnn NoEpAnns
loc (FieldOcc XCFieldOcc GhcPs
_ (L SrcAnn NameAnn
ll RdrName
lbl))
                              , hfbRHS :: forall lhs rhs. HsFieldBind lhs rhs -> rhs
hfbRHS = LocatedA arg
arg
                              , hfbPun :: forall lhs rhs. HsFieldBind lhs rhs -> Bool
hfbPun = Bool
pun }))
      = do { Name
sel <- SrcAnn NoEpAnns -> RnM Name -> RnM Name
forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
setSrcSpanA SrcAnn NoEpAnns
loc (RnM Name -> RnM Name) -> RnM Name -> RnM Name
forall a b. (a -> b) -> a -> b
$ Maybe Name -> RdrName -> RnM Name
lookupRecFieldOcc Maybe Name
parent RdrName
lbl
           ; let arg_rdr :: RdrName
arg_rdr = OccName -> RdrName
mkRdrUnqual (OccName -> RdrName) -> OccName -> RdrName
forall a b. (a -> b) -> a -> b
$ HasDebugCallStack => OccName -> OccName
OccName -> OccName
recFieldToVarOcc (OccName -> OccName) -> OccName -> OccName
forall a b. (a -> b) -> a -> b
$ Name -> OccName
forall name. HasOccName name => name -> OccName
occName Name
sel
                 -- Discard any module qualifier (#11662)
           ; LocatedA arg
arg' <- if Bool
pun
                     then do { Bool -> TcRnMessage -> RnM ()
checkErr Bool
pun_ok (TcRnMessage -> RnM ()) -> TcRnMessage -> RnM ()
forall a b. (a -> b) -> a -> b
$
                                Located RdrName -> TcRnMessage
TcRnIllegalFieldPunning (SrcSpan -> RdrName -> Located RdrName
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcSpan
forall a. SrcSpanAnn' a -> SrcSpan
locA SrcAnn NoEpAnns
loc) RdrName
arg_rdr)
                             ; LocatedA arg -> IOEnv (Env TcGblEnv TcLclEnv) (LocatedA arg)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (LocatedA arg -> IOEnv (Env TcGblEnv TcLclEnv) (LocatedA arg))
-> LocatedA arg -> IOEnv (Env TcGblEnv TcLclEnv) (LocatedA arg)
forall a b. (a -> b) -> a -> b
$ SrcSpanAnnA -> arg -> LocatedA arg
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcSpanAnnA
forall a ann. SrcSpanAnn' a -> SrcAnn ann
l2l SrcAnn NoEpAnns
loc) (arg -> LocatedA arg) -> arg -> LocatedA arg
forall a b. (a -> b) -> a -> b
$
                                 SrcSpan -> RdrName -> arg
mk_arg (SrcAnn NoEpAnns -> SrcSpan
forall a. SrcSpanAnn' a -> SrcSpan
locA SrcAnn NoEpAnns
loc) RdrName
arg_rdr }
                     else LocatedA arg -> IOEnv (Env TcGblEnv TcLclEnv) (LocatedA arg)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return LocatedA arg
arg
           ; GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)))
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
 -> IOEnv
      (Env TcGblEnv TcLclEnv)
      (GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))))
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)))
forall a b. (a -> b) -> a -> b
$ SrcSpanAnnA
-> HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
forall l e. l -> e -> GenLocated l e
L SrcSpanAnnA
l (HsFieldBind
   (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)
 -> GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)))
-> HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
forall a b. (a -> b) -> a -> b
$
               HsFieldBind
                 { hfbAnn :: XHsFieldBind (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
hfbAnn = XHsFieldBind (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
EpAnn [AddEpAnn]
forall a. EpAnn a
noAnn
                 , hfbLHS :: GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)
hfbLHS = SrcAnn NoEpAnns
-> FieldOcc GhcRn -> GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)
forall l e. l -> e -> GenLocated l e
L SrcAnn NoEpAnns
loc (XCFieldOcc GhcRn -> XRec GhcRn RdrName -> FieldOcc GhcRn
forall pass. XCFieldOcc pass -> XRec pass RdrName -> FieldOcc pass
FieldOcc XCFieldOcc GhcRn
Name
sel (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L SrcAnn NameAnn
ll RdrName
arg_rdr))
                 , hfbRHS :: LocatedA arg
hfbRHS = LocatedA arg
arg'
                 , hfbPun :: Bool
hfbPun = Bool
pun } }

    rn_dotdot :: Maybe (Located RecFieldsDotDot)      -- See Note [DotDot fields] in GHC.Hs.Pat
              -> Maybe Name -- The constructor (Nothing for an
                                --    out of scope constructor)
              -> [LHsRecField GhcRn (LocatedA arg)] -- Explicit fields
              -> RnM ([LHsRecField GhcRn (LocatedA arg)])   -- Field Labels we need to fill in
    rn_dotdot :: Maybe (GenLocated SrcSpan RecFieldsDotDot)
-> Maybe Name
-> [LHsRecField GhcRn (LocatedA arg)]
-> RnM [LHsRecField GhcRn (LocatedA arg)]
rn_dotdot (Just (L SrcSpan
loc (RecFieldsDotDot Int
n))) (Just Name
con) [LHsRecField GhcRn (LocatedA arg)]
flds -- ".." on record construction / pat match
      | Bool -> Bool
not (Name -> Bool
isUnboundName Name
con) -- This test is because if the constructor
                                -- isn't in scope the constructor lookup will add
                                -- an error but still return an unbound name. We
                                -- don't want that to screw up the dot-dot fill-in stuff.
      = Bool
-> RnM [LHsRecField GhcRn (LocatedA arg)]
-> RnM [LHsRecField GhcRn (LocatedA arg)]
forall a. HasCallStack => Bool -> a -> a
assert ([LHsRecField GhcRn (LocatedA arg)]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
flds [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> Int -> Bool
forall a. [a] -> Int -> Bool
`lengthIs` Int
n) (RnM [LHsRecField GhcRn (LocatedA arg)]
 -> RnM [LHsRecField GhcRn (LocatedA arg)])
-> RnM [LHsRecField GhcRn (LocatedA arg)]
-> RnM [LHsRecField GhcRn (LocatedA arg)]
forall a b. (a -> b) -> a -> b
$
        do { Bool
dd_flag <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.RecordWildCards
           ; Bool -> TcRnMessage -> RnM ()
checkErr Bool
dd_flag (HsRecFieldContext -> TcRnMessage
needFlagDotDot HsRecFieldContext
ctxt)
           ; (GlobalRdrEnv
rdr_env, LocalRdrEnv
lcl_env) <- TcRn (GlobalRdrEnv, LocalRdrEnv)
getRdrEnvs
           ; ConInfo
conInfo <- HasDebugCallStack => Name -> RnM ConInfo
Name -> RnM ConInfo
lookupConstructorInfo Name
con
           ; Bool -> RnM () -> RnM ()
forall (f :: * -> *). Applicative f => Bool -> f () -> f ()
when (ConInfo
conInfo ConInfo -> ConInfo -> Bool
forall a. Eq a => a -> a -> Bool
== ConInfo
ConHasPositionalArgs) (TcRnMessage -> RnM ()
addErr (Name -> TcRnMessage
TcRnIllegalWildcardsInConstructor Name
con))
           ; let present_flds :: OccSet
present_flds = [OccName] -> OccSet
mkOccSet ([OccName] -> OccSet) -> [OccName] -> OccSet
forall a b. (a -> b) -> a -> b
$ (RdrName -> OccName) -> [RdrName] -> [OccName]
forall a b. (a -> b) -> [a] -> [b]
map RdrName -> OccName
rdrNameOcc ([LHsRecField GhcRn (LocatedA arg)] -> [RdrName]
forall p arg. UnXRec p => [LHsRecField p arg] -> [RdrName]
getFieldLbls [LHsRecField GhcRn (LocatedA arg)]
flds)

                   -- For constructor uses (but not patterns)
                   -- the arg should be in scope locally;
                   -- i.e. not top level or imported
                   -- Eg.  data R = R { x,y :: Int }
                   --      f x = R { .. }   -- Should expand to R {x=x}, not R{x=x,y=y}
                 arg_in_scope :: OccName -> Bool
arg_in_scope OccName
lbl = OccName -> RdrName
mkRdrUnqual OccName
lbl RdrName -> LocalRdrEnv -> Bool
`elemLocalRdrEnv` LocalRdrEnv
lcl_env

                 ([FieldLabel]
dot_dot_fields, [FieldGlobalRdrElt]
dot_dot_gres) =
                   [(FieldLabel, FieldGlobalRdrElt)]
-> ([FieldLabel], [FieldGlobalRdrElt])
forall a b. [(a, b)] -> ([a], [b])
unzip [ (FieldLabel
fl, FieldGlobalRdrElt
gre)
                         | FieldLabel
fl <- ConInfo -> [FieldLabel]
conInfoFields ConInfo
conInfo
                         , let lbl :: OccName
lbl = HasDebugCallStack => OccName -> OccName
OccName -> OccName
recFieldToVarOcc (OccName -> OccName) -> OccName -> OccName
forall a b. (a -> b) -> a -> b
$ Name -> OccName
forall name. HasOccName name => name -> OccName
occName (Name -> OccName) -> Name -> OccName
forall a b. (a -> b) -> a -> b
$ FieldLabel -> Name
flSelector FieldLabel
fl
                         , Bool -> Bool
not (OccName
lbl OccName -> OccSet -> Bool
`elemOccSet` OccSet
present_flds)
                         , Just FieldGlobalRdrElt
gre <- [GlobalRdrEnv -> FieldLabel -> Maybe FieldGlobalRdrElt
lookupGRE_FieldLabel GlobalRdrEnv
rdr_env FieldLabel
fl]
                                       -- Check selector is in scope
                         , case HsRecFieldContext
ctxt of
                             HsRecFieldCon {} -> OccName -> Bool
arg_in_scope OccName
lbl
                             HsRecFieldContext
_other           -> Bool
True ]

           ; DeprecationWarnings -> [FieldGlobalRdrElt] -> RnM ()
addUsedGREs DeprecationWarnings
NoDeprecationWarnings [FieldGlobalRdrElt]
dot_dot_gres
           ; let locn :: SrcSpanAnnA
locn = SrcSpan -> SrcSpanAnnA
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
loc
           ; [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return [ SrcSpanAnnA
-> HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg)
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcSpanAnnA
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
loc) (HsFieldBind
                        { hfbAnn :: XHsFieldBind (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
hfbAnn = XHsFieldBind (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn))
EpAnn [AddEpAnn]
forall a. EpAnn a
noAnn
                        , hfbLHS :: GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)
hfbLHS
                           = SrcAnn NoEpAnns
-> FieldOcc GhcRn -> GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcAnn NoEpAnns
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
loc) (XCFieldOcc GhcRn -> XRec GhcRn RdrName -> FieldOcc GhcRn
forall pass. XCFieldOcc pass -> XRec pass RdrName -> FieldOcc pass
FieldOcc XCFieldOcc GhcRn
Name
sel (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L (SrcSpan -> SrcAnn NameAnn
forall ann. SrcSpan -> SrcAnn ann
noAnnSrcSpan SrcSpan
loc) RdrName
arg_rdr))
                        , hfbRHS :: LocatedA arg
hfbRHS = SrcSpanAnnA -> arg -> LocatedA arg
forall l e. l -> e -> GenLocated l e
L SrcSpanAnnA
locn (SrcSpan -> RdrName -> arg
mk_arg SrcSpan
loc RdrName
arg_rdr)
                        , hfbPun :: Bool
hfbPun = Bool
False })
                    | FieldLabel
fl <- [FieldLabel]
dot_dot_fields
                    , let sel :: Name
sel     = FieldLabel -> Name
flSelector FieldLabel
fl
                          arg_rdr :: RdrName
arg_rdr = OccName -> RdrName
mkRdrUnqual
                                  (OccName -> RdrName) -> OccName -> RdrName
forall a b. (a -> b) -> a -> b
$ HasDebugCallStack => OccName -> OccName
OccName -> OccName
recFieldToVarOcc
                                  (OccName -> OccName) -> OccName -> OccName
forall a b. (a -> b) -> a -> b
$ Name -> OccName
nameOccName Name
sel ] }

    rn_dotdot Maybe (GenLocated SrcSpan RecFieldsDotDot)
_dotdot Maybe Name
_mb_con [LHsRecField GhcRn (LocatedA arg)]
_flds
      = [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     [GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (FieldOcc GhcRn)) (LocatedA arg))]
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return []
      -- _dotdot = Nothing => No ".." at all
      -- _mb_con = Nothing => Record update
      -- _mb_con = Just unbound => Out of scope data constructor

    dup_flds :: [NE.NonEmpty RdrName]
        -- Each list represents a RdrName that occurred more than once
        -- (the list contains all occurrences)
        -- Each list in dup_fields is non-empty
    ([RdrName]
_, [NonEmpty RdrName]
dup_flds) = (RdrName -> RdrName -> Ordering)
-> [RdrName] -> ([RdrName], [NonEmpty RdrName])
forall a. (a -> a -> Ordering) -> [a] -> ([a], [NonEmpty a])
removeDups (FastString -> FastString -> Ordering
uniqCompareFS (FastString -> FastString -> Ordering)
-> (RdrName -> FastString) -> RdrName -> RdrName -> Ordering
forall b c a. (b -> b -> c) -> (a -> b) -> a -> a -> c
`on` (OccName -> FastString
occNameFS (OccName -> FastString)
-> (RdrName -> OccName) -> RdrName -> FastString
forall b c a. (b -> c) -> (a -> b) -> a -> c
. RdrName -> OccName
rdrNameOcc)) ([LHsRecField GhcPs (LocatedA arg)] -> [RdrName]
forall p arg. UnXRec p => [LHsRecField p arg] -> [RdrName]
getFieldLbls [LHsRecField GhcPs (LocatedA arg)]
flds)
      -- See the same duplicate handling logic in rnHsRecUpdFields below for further context.

-- | Rename a regular (non-overloaded) record field update,
-- disambiguating the fields if necessary.
rnHsRecUpdFields
    :: [LHsRecUpdField GhcPs GhcPs]
    -> RnM (XLHsRecUpdLabels GhcRn, [LHsRecUpdField GhcRn GhcRn], FreeVars)
rnHsRecUpdFields :: [LHsRecUpdField GhcPs GhcPs]
-> RnM
     (XLHsRecUpdLabels GhcRn, [LHsRecUpdField GhcRn GhcRn], FreeVars)
rnHsRecUpdFields [LHsRecUpdField GhcPs GhcPs]
flds
  = do { Bool
pun_ok <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.NamedFieldPuns

       -- Check for an empty record update:  e {}
       -- NB: don't complain about e { .. }, because rn_dotdot has done that already
       ; case [LHsRecUpdField GhcPs GhcPs]
flds of
          { [] -> TcRnMessage
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (NonEmpty (HsRecUpdParent GhcRn),
      [GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
      FreeVars)
forall a. TcRnMessage -> TcM a
failWithTc TcRnMessage
TcRnEmptyRecordUpdate
          ; LHsRecUpdField GhcPs GhcPs
fld:[LHsRecUpdField GhcPs GhcPs]
other_flds ->
    do { let dup_lbls :: [NE.NonEmpty RdrName]
             ([RdrName]
_, [NonEmpty RdrName]
dup_lbls) = (RdrName -> RdrName -> Ordering)
-> [RdrName] -> ([RdrName], [NonEmpty RdrName])
forall a. (a -> a -> Ordering) -> [a] -> ([a], [NonEmpty a])
removeDups (FastString -> FastString -> Ordering
uniqCompareFS (FastString -> FastString -> Ordering)
-> (RdrName -> FastString) -> RdrName -> RdrName -> Ordering
forall b c a. (b -> b -> c) -> (a -> b) -> a -> a -> c
`on` (OccName -> FastString
occNameFS (OccName -> FastString)
-> (RdrName -> OccName) -> RdrName -> FastString
forall b c a. (b -> c) -> (a -> b) -> a -> c
. RdrName -> OccName
rdrNameOcc))
                              ((GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
      (LHsExpr GhcPs))
 -> RdrName)
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
         (LHsExpr GhcPs))]
-> [RdrName]
forall a b. (a -> b) -> [a] -> [b]
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (GenLocated (SrcAnn NameAnn) RdrName -> RdrName
forall l e. GenLocated l e -> e
unLoc (GenLocated (SrcAnn NameAnn) RdrName -> RdrName)
-> (GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
         (LHsExpr GhcPs))
    -> GenLocated (SrcAnn NameAnn) RdrName)
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
        (LHsExpr GhcPs))
-> RdrName
forall b c a. (b -> c) -> (a -> b) -> a -> c
. LHsRecUpdField GhcPs GhcPs -> GenLocated (SrcAnn NameAnn) RdrName
GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
     (LHsExpr GhcPs))
-> GenLocated (SrcAnn NameAnn) RdrName
forall (p :: Pass) q.
LHsRecUpdField (GhcPass p) q -> GenLocated (SrcAnn NameAnn) RdrName
getFieldUpdLbl) [LHsRecUpdField GhcPs GhcPs]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
      (LHsExpr GhcPs))]
flds)
               -- NB: we compare using the underlying field label FastString,
               -- in order to catch duplicates involving qualified names,
               -- as in the record update `r { fld = x, Mod.fld = y }`.
               -- See #21959.
               -- Note that this test doesn't correctly handle exact Names, but those
               -- aren't handled properly by the rest of the compiler anyway. See #22122.
       ; (NonEmpty RdrName -> RnM ()) -> [NonEmpty RdrName] -> RnM ()
forall (t :: * -> *) (m :: * -> *) a b.
(Foldable t, Monad m) =>
(a -> m b) -> t a -> m ()
mapM_ (TcRnMessage -> RnM ()
addErr (TcRnMessage -> RnM ())
-> (NonEmpty RdrName -> TcRnMessage) -> NonEmpty RdrName -> RnM ()
forall b c a. (b -> c) -> (a -> b) -> a -> c
. HsRecFieldContext -> NonEmpty RdrName -> TcRnMessage
dupFieldErr HsRecFieldContext
HsRecFieldUpd) [NonEmpty RdrName]
dup_lbls

         -- See Note [Disambiguating record updates]
       ; NonEmpty (HsRecUpdParent GhcRn)
possible_parents <- NonEmpty (LHsRecUpdField GhcPs GhcPs)
-> RnM (NonEmpty (HsRecUpdParent GhcRn))
lookupRecUpdFields (LHsRecUpdField GhcPs GhcPs
GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
     (GenLocated SrcSpanAnnA (HsExpr GhcPs)))
fld GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
     (GenLocated SrcSpanAnnA (HsExpr GhcPs)))
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
         (GenLocated SrcSpanAnnA (HsExpr GhcPs)))]
-> NonEmpty
     (GenLocated
        SrcSpanAnnA
        (HsFieldBind
           (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
           (GenLocated SrcSpanAnnA (HsExpr GhcPs))))
forall a. a -> [a] -> NonEmpty a
NE.:| [LHsRecUpdField GhcPs GhcPs]
[GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcPs))
      (GenLocated SrcSpanAnnA (HsExpr GhcPs)))]
other_flds)
       ; let  mb_unambig_lbls :: Maybe [FieldLabel]
              fvs :: FreeVars
              (Maybe [FieldLabel]
mb_unambig_lbls, FreeVars
fvs) =
               case NonEmpty (HsRecUpdParent GhcRn)
possible_parents of
                  RnRecUpdParent { rnRecUpdLabels :: HsRecUpdParent GhcRn -> NonEmpty FieldGlobalRdrElt
rnRecUpdLabels = NonEmpty FieldGlobalRdrElt
gres } NE.:| []
                    | let lbls :: [FieldLabel]
lbls = (FieldGlobalRdrElt -> FieldLabel)
-> [FieldGlobalRdrElt] -> [FieldLabel]
forall a b. (a -> b) -> [a] -> [b]
map HasDebugCallStack => FieldGlobalRdrElt -> FieldLabel
FieldGlobalRdrElt -> FieldLabel
fieldGRELabel ([FieldGlobalRdrElt] -> [FieldLabel])
-> [FieldGlobalRdrElt] -> [FieldLabel]
forall a b. (a -> b) -> a -> b
$ NonEmpty FieldGlobalRdrElt -> [FieldGlobalRdrElt]
forall a. NonEmpty a -> [a]
NE.toList NonEmpty FieldGlobalRdrElt
gres
                    -> ( [FieldLabel] -> Maybe [FieldLabel]
forall a. a -> Maybe a
Just [FieldLabel]
lbls, [Name] -> FreeVars
mkFVs ([Name] -> FreeVars) -> [Name] -> FreeVars
forall a b. (a -> b) -> a -> b
$ (FieldLabel -> Name) -> [FieldLabel] -> [Name]
forall a b. (a -> b) -> [a] -> [b]
map FieldLabel -> Name
flSelector [FieldLabel]
lbls)
                  NonEmpty (HsRecUpdParent GhcRn)
_ -> ( Maybe [FieldLabel]
forall a. Maybe a
Nothing
                       , [FreeVars] -> FreeVars
plusFVs ([FreeVars] -> FreeVars) -> [FreeVars] -> FreeVars
forall a b. (a -> b) -> a -> b
$ (HsRecUpdParent GhcRn -> FreeVars)
-> [HsRecUpdParent GhcRn] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map ([FreeVars] -> FreeVars
plusFVs ([FreeVars] -> FreeVars)
-> (HsRecUpdParent GhcRn -> [FreeVars])
-> HsRecUpdParent GhcRn
-> FreeVars
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (FieldGlobalRdrElt -> FreeVars)
-> [FieldGlobalRdrElt] -> [FreeVars]
forall a b. (a -> b) -> [a] -> [b]
map FieldGlobalRdrElt -> FreeVars
pat_syn_free_vars ([FieldGlobalRdrElt] -> [FreeVars])
-> (HsRecUpdParent GhcRn -> [FieldGlobalRdrElt])
-> HsRecUpdParent GhcRn
-> [FreeVars]
forall b c a. (b -> c) -> (a -> b) -> a -> c
. NonEmpty FieldGlobalRdrElt -> [FieldGlobalRdrElt]
forall a. NonEmpty a -> [a]
NE.toList (NonEmpty FieldGlobalRdrElt -> [FieldGlobalRdrElt])
-> (HsRecUpdParent GhcRn -> NonEmpty FieldGlobalRdrElt)
-> HsRecUpdParent GhcRn
-> [FieldGlobalRdrElt]
forall b c a. (b -> c) -> (a -> b) -> a -> c
. HsRecUpdParent GhcRn -> NonEmpty FieldGlobalRdrElt
rnRecUpdLabels)
                                 ([HsRecUpdParent GhcRn] -> [FreeVars])
-> [HsRecUpdParent GhcRn] -> [FreeVars]
forall a b. (a -> b) -> a -> b
$ NonEmpty (HsRecUpdParent GhcRn) -> [HsRecUpdParent GhcRn]
forall a. NonEmpty a -> [a]
NE.toList NonEmpty (HsRecUpdParent GhcRn)
possible_parents
                         -- See Note [Using PatSyn FreeVars]
                       )

        -- Rename each field.
        ; ([GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
upd_flds, FreeVars
fvs') <- Bool
-> Maybe [FieldLabel]
-> [LHsRecUpdField GhcPs GhcPs]
-> RnM ([LHsRecUpdField GhcRn GhcRn], FreeVars)
rn_flds Bool
pun_ok Maybe [FieldLabel]
mb_unambig_lbls [LHsRecUpdField GhcPs GhcPs]
flds
        ; let all_fvs :: FreeVars
all_fvs = FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs'
        ; (NonEmpty (HsRecUpdParent GhcRn),
 [GenLocated
    SrcSpanAnnA
    (HsFieldBind
       (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
       (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
 FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     (NonEmpty (HsRecUpdParent GhcRn),
      [GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
      FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (NonEmpty (HsRecUpdParent GhcRn)
possible_parents, [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
upd_flds, FreeVars
all_fvs) } } }

    where

      -- For an ambiguous record update involving pattern synonym record fields,
      -- we must add all the possibly-relevant field selector names to ensure that
      -- we typecheck the record update **after** we typecheck the pattern synonym
      -- definition. See Note [Using PatSyn FreeVars].
      pat_syn_free_vars :: FieldGlobalRdrElt -> FreeVars
      pat_syn_free_vars :: FieldGlobalRdrElt -> FreeVars
pat_syn_free_vars (GRE { gre_info :: forall info. GlobalRdrEltX info -> info
gre_info = GREInfo
info })
        | IAmRecField RecFieldInfo
fld_info <- GREInfo
info
        , RecFieldInfo { recFieldLabel :: RecFieldInfo -> FieldLabel
recFieldLabel = FieldLabel
fl, recFieldCons :: RecFieldInfo -> UniqSet ConLikeName
recFieldCons = UniqSet ConLikeName
cons } <- RecFieldInfo
fld_info
        , (ConLikeName -> Bool) -> UniqSet ConLikeName -> Bool
forall a. (a -> Bool) -> UniqSet a -> Bool
uniqSetAny ConLikeName -> Bool
is_PS UniqSet ConLikeName
cons
        = Name -> FreeVars
unitFV (FieldLabel -> Name
flSelector FieldLabel
fl)
      pat_syn_free_vars FieldGlobalRdrElt
_
        = FreeVars
emptyFVs

      is_PS :: ConLikeName -> Bool
      is_PS :: ConLikeName -> Bool
is_PS (PatSynName  {}) = Bool
True
      is_PS (DataConName {}) = Bool
False

      rn_flds :: Bool -> Maybe [FieldLabel]
              -> [LHsRecUpdField GhcPs GhcPs]
              -> RnM ([LHsRecUpdField GhcRn GhcRn], FreeVars)
      rn_flds :: Bool
-> Maybe [FieldLabel]
-> [LHsRecUpdField GhcPs GhcPs]
-> RnM ([LHsRecUpdField GhcRn GhcRn], FreeVars)
rn_flds Bool
_ Maybe [FieldLabel]
_ [] = ([GenLocated
    SrcSpanAnnA
    (HsFieldBind
       (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
       (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
 FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
      FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ([], FreeVars
emptyFVs)
      rn_flds Bool
pun_ok Maybe [FieldLabel]
mb_unambig_lbls
              ((L SrcSpanAnnA
l (HsFieldBind { hfbLHS :: forall lhs rhs. HsFieldBind lhs rhs -> lhs
hfbLHS = L SrcAnn NoEpAnns
loc AmbiguousFieldOcc GhcPs
f
                                 , hfbRHS :: forall lhs rhs. HsFieldBind lhs rhs -> rhs
hfbRHS = GenLocated SrcSpanAnnA (HsExpr GhcPs)
arg
                                 , hfbPun :: forall lhs rhs. HsFieldBind lhs rhs -> Bool
hfbPun = Bool
pun })):[LHsRecUpdField GhcPs GhcPs]
flds)
        = do { let lbl :: RdrName
lbl = AmbiguousFieldOcc GhcPs -> RdrName
forall (p :: Pass). AmbiguousFieldOcc (GhcPass p) -> RdrName
ambiguousFieldOccRdrName AmbiguousFieldOcc GhcPs
f
             ; (LHsExpr GhcPs
arg' :: LHsExpr GhcPs) <- if Bool
pun
                       then do { SrcAnn NoEpAnns -> RnM () -> RnM ()
forall ann a. SrcSpanAnn' ann -> TcRn a -> TcRn a
setSrcSpanA SrcAnn NoEpAnns
loc (RnM () -> RnM ()) -> RnM () -> RnM ()
forall a b. (a -> b) -> a -> b
$
                                 Bool -> TcRnMessage -> RnM ()
checkErr Bool
pun_ok (Located RdrName -> TcRnMessage
TcRnIllegalFieldPunning (SrcSpan -> RdrName -> Located RdrName
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcSpan
forall a. SrcSpanAnn' a -> SrcSpan
locA SrcAnn NoEpAnns
loc) RdrName
lbl))
                                 -- Discard any module qualifier (#11662)
                               ; let arg_rdr :: RdrName
arg_rdr = OccName -> RdrName
mkRdrUnqual (RdrName -> OccName
rdrNameOcc RdrName
lbl)
                               ; GenLocated SrcSpanAnnA (HsExpr GhcPs)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated SrcSpanAnnA (HsExpr GhcPs))
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (SrcSpanAnnA
-> HsExpr GhcPs -> GenLocated SrcSpanAnnA (HsExpr GhcPs)
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcSpanAnnA
forall a ann. SrcSpanAnn' a -> SrcAnn ann
l2l SrcAnn NoEpAnns
loc) (XVar GhcPs -> XRec GhcPs (IdP GhcPs) -> HsExpr GhcPs
forall p. XVar p -> LIdP p -> HsExpr p
HsVar XVar GhcPs
NoExtField
noExtField (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcAnn NameAnn
forall a ann. SrcSpanAnn' a -> SrcAnn ann
l2l SrcAnn NoEpAnns
loc) RdrName
arg_rdr))) }
                       else GenLocated SrcSpanAnnA (HsExpr GhcPs)
-> IOEnv
     (Env TcGblEnv TcLclEnv) (GenLocated SrcSpanAnnA (HsExpr GhcPs))
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return GenLocated SrcSpanAnnA (HsExpr GhcPs)
arg
             ; (GenLocated SrcSpanAnnA (HsExpr GhcRn)
arg'', FreeVars
fvs) <- LHsExpr GhcPs -> RnM (LHsExpr GhcRn, FreeVars)
rnLExpr LHsExpr GhcPs
arg'
             ; let lbl' :: AmbiguousFieldOcc GhcRn
                   lbl' :: AmbiguousFieldOcc GhcRn
lbl' = case Maybe [FieldLabel]
mb_unambig_lbls of
                            { Just (FieldLabel
fl:[FieldLabel]
_) ->
                                let sel_name :: Name
sel_name = FieldLabel -> Name
flSelector FieldLabel
fl
                                in XUnambiguous GhcRn -> XRec GhcRn RdrName -> AmbiguousFieldOcc GhcRn
forall pass.
XUnambiguous pass -> XRec pass RdrName -> AmbiguousFieldOcc pass
Unambiguous XUnambiguous GhcRn
Name
sel_name   (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcAnn NameAnn
forall a ann. SrcSpanAnn' a -> SrcAnn ann
l2l SrcAnn NoEpAnns
loc) RdrName
lbl)
                            ; Maybe [FieldLabel]
_ ->   XAmbiguous GhcRn -> XRec GhcRn RdrName -> AmbiguousFieldOcc GhcRn
forall pass.
XAmbiguous pass -> XRec pass RdrName -> AmbiguousFieldOcc pass
Ambiguous XAmbiguous GhcRn
NoExtField
noExtField (SrcAnn NameAnn -> RdrName -> GenLocated (SrcAnn NameAnn) RdrName
forall l e. l -> e -> GenLocated l e
L (SrcAnn NoEpAnns -> SrcAnn NameAnn
forall a ann. SrcSpanAnn' a -> SrcAnn ann
l2l SrcAnn NoEpAnns
loc) RdrName
lbl) }
                   fld' :: LHsRecUpdField GhcRn GhcRn
                   fld' :: LHsRecUpdField GhcRn GhcRn
fld' = SrcSpanAnnA
-> HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
     (GenLocated SrcSpanAnnA (HsExpr GhcRn))
-> GenLocated
     SrcSpanAnnA
     (HsFieldBind
        (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
        (GenLocated SrcSpanAnnA (HsExpr GhcRn)))
forall l e. l -> e -> GenLocated l e
L SrcSpanAnnA
l (HsFieldBind { hfbAnn :: XHsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
hfbAnn = XHsFieldBind
  (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
EpAnn [AddEpAnn]
forall a. EpAnn a
noAnn
                                           , hfbLHS :: GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn)
hfbLHS = SrcAnn NoEpAnns
-> AmbiguousFieldOcc GhcRn
-> GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn)
forall l e. l -> e -> GenLocated l e
L SrcAnn NoEpAnns
loc AmbiguousFieldOcc GhcRn
lbl'
                                           , hfbRHS :: GenLocated SrcSpanAnnA (HsExpr GhcRn)
hfbRHS = GenLocated SrcSpanAnnA (HsExpr GhcRn)
arg''
                                           , hfbPun :: Bool
hfbPun = Bool
pun })
             ; ([GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
flds', FreeVars
fvs') <- Bool
-> Maybe [FieldLabel]
-> [LHsRecUpdField GhcPs GhcPs]
-> RnM ([LHsRecUpdField GhcRn GhcRn], FreeVars)
rn_flds Bool
pun_ok ([FieldLabel] -> [FieldLabel]
forall a. HasCallStack => [a] -> [a]
tail ([FieldLabel] -> [FieldLabel])
-> Maybe [FieldLabel] -> Maybe [FieldLabel]
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
<$> Maybe [FieldLabel]
mb_unambig_lbls) [LHsRecUpdField GhcPs GhcPs]
flds
             ; ([GenLocated
    SrcSpanAnnA
    (HsFieldBind
       (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
       (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
 FreeVars)
-> IOEnv
     (Env TcGblEnv TcLclEnv)
     ([GenLocated
         SrcSpanAnnA
         (HsFieldBind
            (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
            (GenLocated SrcSpanAnnA (HsExpr GhcRn)))],
      FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return (LHsRecUpdField GhcRn GhcRn
GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
     (GenLocated SrcSpanAnnA (HsExpr GhcRn)))
fld' GenLocated
  SrcSpanAnnA
  (HsFieldBind
     (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
     (GenLocated SrcSpanAnnA (HsExpr GhcRn)))
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
         (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
-> [GenLocated
      SrcSpanAnnA
      (HsFieldBind
         (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
         (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
forall a. a -> [a] -> [a]
: [GenLocated
   SrcSpanAnnA
   (HsFieldBind
      (GenLocated (SrcAnn NoEpAnns) (AmbiguousFieldOcc GhcRn))
      (GenLocated SrcSpanAnnA (HsExpr GhcRn)))]
flds', FreeVars
fvs FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs') }

getFieldIds :: [LHsRecField GhcRn arg] -> [Name]
getFieldIds :: forall arg. [LHsRecField GhcRn arg] -> [Name]
getFieldIds [LHsRecField GhcRn arg]
flds = (GenLocated
   SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)
 -> Name)
-> [GenLocated
      SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)]
-> [Name]
forall a b. (a -> b) -> [a] -> [b]
map (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg -> XCFieldOcc GhcRn
HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg -> Name
forall p arg. UnXRec p => HsRecField p arg -> XCFieldOcc p
hsRecFieldSel (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg -> Name)
-> (GenLocated
      SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)
    -> HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)
-> GenLocated
     SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)
-> Name
forall b c a. (b -> c) -> (a -> b) -> a -> c
. GenLocated
  SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)
-> HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg
forall l e. GenLocated l e -> e
unLoc) [LHsRecField GhcRn arg]
[GenLocated
   SrcSpanAnnA (HsFieldBind (XRec GhcRn (FieldOcc GhcRn)) arg)]
flds

getFieldLbls :: forall p arg . UnXRec p => [LHsRecField p arg] -> [RdrName]
getFieldLbls :: forall p arg. UnXRec p => [LHsRecField p arg] -> [RdrName]
getFieldLbls [LHsRecField p arg]
flds
  = (LHsRecField p arg -> RdrName) -> [LHsRecField p arg] -> [RdrName]
forall a b. (a -> b) -> [a] -> [b]
map (forall p a. UnXRec p => XRec p a -> a
unXRec @p (XRec p RdrName -> RdrName)
-> (LHsRecField p arg -> XRec p RdrName)
-> LHsRecField p arg
-> RdrName
forall b c a. (b -> c) -> (a -> b) -> a -> c
. FieldOcc p -> XRec p RdrName
forall pass. FieldOcc pass -> XRec pass RdrName
foLabel (FieldOcc p -> XRec p RdrName)
-> (LHsRecField p arg -> FieldOcc p)
-> LHsRecField p arg
-> XRec p RdrName
forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall p a. UnXRec p => XRec p a -> a
unXRec @p (XRec p (FieldOcc p) -> FieldOcc p)
-> (LHsRecField p arg -> XRec p (FieldOcc p))
-> LHsRecField p arg
-> FieldOcc p
forall b c a. (b -> c) -> (a -> b) -> a -> c
. HsFieldBind (XRec p (FieldOcc p)) arg -> XRec p (FieldOcc p)
forall lhs rhs. HsFieldBind lhs rhs -> lhs
hfbLHS (HsFieldBind (XRec p (FieldOcc p)) arg -> XRec p (FieldOcc p))
-> (LHsRecField p arg -> HsFieldBind (XRec p (FieldOcc p)) arg)
-> LHsRecField p arg
-> XRec p (FieldOcc p)
forall b c a. (b -> c) -> (a -> b) -> a -> c
. forall p a. UnXRec p => XRec p a -> a
unXRec @p) [LHsRecField p arg]
flds

needFlagDotDot :: HsRecFieldContext -> TcRnMessage
needFlagDotDot :: HsRecFieldContext -> TcRnMessage
needFlagDotDot = RecordFieldPart -> TcRnMessage
TcRnIllegalWildcardsInRecord (RecordFieldPart -> TcRnMessage)
-> (HsRecFieldContext -> RecordFieldPart)
-> HsRecFieldContext
-> TcRnMessage
forall b c a. (b -> c) -> (a -> b) -> a -> c
. HsRecFieldContext -> RecordFieldPart
toRecordFieldPart

dupFieldErr :: HsRecFieldContext -> NE.NonEmpty RdrName -> TcRnMessage
dupFieldErr :: HsRecFieldContext -> NonEmpty RdrName -> TcRnMessage
dupFieldErr HsRecFieldContext
ctxt = RecordFieldPart -> NonEmpty RdrName -> TcRnMessage
TcRnDuplicateFieldName (HsRecFieldContext -> RecordFieldPart
toRecordFieldPart HsRecFieldContext
ctxt)

toRecordFieldPart :: HsRecFieldContext -> RecordFieldPart
toRecordFieldPart :: HsRecFieldContext -> RecordFieldPart
toRecordFieldPart (HsRecFieldCon Name
n)  = Name -> RecordFieldPart
RecordFieldConstructor Name
n
toRecordFieldPart (HsRecFieldPat Name
n)  = Name -> RecordFieldPart
RecordFieldPattern     Name
n
toRecordFieldPart (HsRecFieldUpd {}) = RecordFieldPart
RecordFieldUpdate

{- Note [Disambiguating record updates]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
When the -XDuplicateRecordFields extension is used, to rename and typecheck
a non-overloaded record update, we might need to disambiguate the field labels.

Consider the following definitions:

   {-# LANGUAGE DuplicateRecordFields #-}

    data R = MkR1 { fld1 :: Int, fld2 :: Char }
           | MKR2 { fld1 :: Int, fld2 :: Char, fld3 :: Bool }
    data S = MkS1 { fld1 :: Int } | MkS2 { fld2 :: Char }

In a record update, the `lookupRecUpdFields` function tries to determine
the parent datatype by computing the parents (TyCon/PatSyn) which have
at least one constructor (DataCon/PatSyn) with all of the fields.

For example, in the (non-overloaded) record update

    r { fld1 = 3, fld2 = 'x' }

only the TyCon R contains at least one DataCon which has both of the fields
being updated: in this case, MkR1 and MkR2 have both of the updated fields.
The TyCon S also has both fields fld1 and fld2, but no single constructor
has both of those fields, so S is not a valid parent for this record update.

Note that this check is namespace-aware, so that a record update such as

    import qualified M ( R (fld1, fld2) )
    f r = r { M.fld1 = 3 }

is unambiguous, as only R contains the field fld1 in the M namespace.
(See however #22122 for issues relating to the usage of exact Names in
record fields.)

See also Note [Type-directed record disambiguation] in GHC.Tc.Gen.Expr.

Note [Using PatSyn FreeVars]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
When we are disambiguating a non-overloaded record update, as per
Note [Disambiguating record updates], and have determined that this
record update might involve pattern synonym record fields, it is important
to declare usage of all these pattern synonyms record fields in the returned
FreeVars of rnHsRecUpdFields. This ensures that the typechecker sees
that the typechecking of the record update depends on the typechecking
of the pattern synonym, and typechecks the pattern synonyms first.
Not doing so caused #21898.

Note that this can be removed once GHC proposal #366 is implemented,
as we will be able to fully disambiguate the record update in the renamer,
and can immediately declare the correct used FreeVars instead of having
to over-estimate in case of ambiguity.

************************************************************************
*                                                                      *
\subsubsection{Literals}
*                                                                      *
************************************************************************

When literals occur we have to make sure
that the types and classes they involve
are made available.
-}

rnLit :: HsLit p -> RnM ()
rnLit :: forall p. HsLit p -> RnM ()
rnLit (HsChar XHsChar p
_ Char
c) = Bool -> TcRnMessage -> RnM ()
checkErr (Char -> Bool
inCharRange Char
c) (Char -> TcRnMessage
TcRnCharLiteralOutOfRange Char
c)
rnLit HsLit p
_ = () -> RnM ()
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ()

-- | Turn a Fractional-looking literal which happens to be an integer into an
-- Integer-looking literal.
-- We only convert numbers where the exponent is between 0 and 100 to avoid
-- converting huge numbers and incurring long compilation times. See #15646.
generalizeOverLitVal :: OverLitVal -> OverLitVal
generalizeOverLitVal :: OverLitVal -> OverLitVal
generalizeOverLitVal (HsFractional fl :: FractionalLit
fl@(FL {fl_text :: FractionalLit -> SourceText
fl_text=SourceText
src,fl_neg :: FractionalLit -> Bool
fl_neg=Bool
neg,fl_exp :: FractionalLit -> Integer
fl_exp=Integer
e}))
    | Integer
e Integer -> Integer -> Bool
forall a. Ord a => a -> a -> Bool
>= -Integer
100 Bool -> Bool -> Bool
&& Integer
e Integer -> Integer -> Bool
forall a. Ord a => a -> a -> Bool
<= Integer
100
    , let val :: Rational
val = FractionalLit -> Rational
rationalFromFractionalLit FractionalLit
fl
    , Rational -> Integer
forall a. Ratio a -> a
denominator Rational
val Integer -> Integer -> Bool
forall a. Eq a => a -> a -> Bool
== Integer
1 = IntegralLit -> OverLitVal
HsIntegral (IL {il_text :: SourceText
il_text=SourceText
src,il_neg :: Bool
il_neg=Bool
neg,il_value :: Integer
il_value=Rational -> Integer
forall a. Ratio a -> a
numerator Rational
val})
generalizeOverLitVal OverLitVal
lit = OverLitVal
lit

isNegativeZeroOverLit :: (XXOverLit t ~ DataConCantHappen) => HsOverLit t -> Bool
isNegativeZeroOverLit :: forall t. (XXOverLit t ~ DataConCantHappen) => HsOverLit t -> Bool
isNegativeZeroOverLit HsOverLit t
lit
 = case HsOverLit t -> OverLitVal
forall p. HsOverLit p -> OverLitVal
ol_val HsOverLit t
lit of
        HsIntegral IntegralLit
i    -> Integer
0 Integer -> Integer -> Bool
forall a. Eq a => a -> a -> Bool
== IntegralLit -> Integer
il_value IntegralLit
i Bool -> Bool -> Bool
&& IntegralLit -> Bool
il_neg IntegralLit
i
        -- For HsFractional, the value of fl is n * (b ^^ e) so it is sufficient
        -- to check if n = 0. b is equal to either 2 or 10. We don't call
        -- rationalFromFractionalLit here as it is expensive when e is big.
        HsFractional FractionalLit
fl -> Rational
0 Rational -> Rational -> Bool
forall a. Eq a => a -> a -> Bool
== FractionalLit -> Rational
fl_signi FractionalLit
fl Bool -> Bool -> Bool
&& FractionalLit -> Bool
fl_neg FractionalLit
fl
        OverLitVal
_               -> Bool
False

{-
Note [Negative zero]
~~~~~~~~~~~~~~~~~~~~~~~~~
There were problems with negative zero in conjunction with Negative Literals
extension. Numeric literal value is contained in Integer and Rational types
inside IntegralLit and FractionalLit. These types cannot represent negative
zero value. So we had to add explicit field 'neg' which would hold information
about literal sign. Here in rnOverLit we use it to detect negative zeroes and
in this case return not only literal itself but also negateName so that users
can apply it explicitly. In this case it stays negative zero.  #13211
-}

rnOverLit :: (XXOverLit t ~ DataConCantHappen) => HsOverLit t ->
             RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
rnOverLit :: forall t.
(XXOverLit t ~ DataConCantHappen) =>
HsOverLit t
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
rnOverLit HsOverLit t
origLit
  = do  { Bool
opt_NumDecimals <- Extension -> RnM Bool
forall gbl lcl. Extension -> TcRnIf gbl lcl Bool
xoptM Extension
LangExt.NumDecimals
        ; let { lit :: HsOverLit t
lit@(OverLit {ol_val :: forall p. HsOverLit p -> OverLitVal
ol_val=OverLitVal
val})
            | Bool
opt_NumDecimals = HsOverLit t
origLit {ol_val = generalizeOverLitVal (ol_val origLit)}
            | Bool
otherwise       = HsOverLit t
origLit
          }
        ; let std_name :: Name
std_name = OverLitVal -> Name
hsOverLitName OverLitVal
val
        ; (Name
from_thing_name, FreeVars
fvs1) <- Name -> RnM (Name, FreeVars)
lookupSyntaxName Name
std_name
        ; let rebindable :: Bool
rebindable = Name
from_thing_name Name -> Name -> Bool
forall a. Eq a => a -> a -> Bool
/= Name
std_name
              lit' :: HsOverLit GhcRn
lit' = HsOverLit t
lit { ol_ext = OverLitRn { ol_rebindable = rebindable
                                              , ol_from_fun = noLocA from_thing_name } }
        ; if HsOverLit GhcRn -> Bool
forall t. (XXOverLit t ~ DataConCantHappen) => HsOverLit t -> Bool
isNegativeZeroOverLit HsOverLit GhcRn
lit'
          then do { (HsExpr GhcRn
negate_name, FreeVars
fvs2) <- Name -> RnM (HsExpr GhcRn, FreeVars)
lookupSyntaxExpr Name
negateName
                  ; ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ((HsOverLit GhcRn
lit' { ol_val = negateOverLitVal val }, HsExpr GhcRn -> Maybe (HsExpr GhcRn)
forall a. a -> Maybe a
Just HsExpr GhcRn
negate_name)
                                  , FreeVars
fvs1 FreeVars -> FreeVars -> FreeVars
`plusFV` FreeVars
fvs2) }
          else ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
-> RnM ((HsOverLit GhcRn, Maybe (HsExpr GhcRn)), FreeVars)
forall a. a -> IOEnv (Env TcGblEnv TcLclEnv) a
forall (m :: * -> *) a. Monad m => a -> m a
return ((HsOverLit GhcRn
lit', Maybe (HsExpr GhcRn)
forall a. Maybe a
Nothing), FreeVars
fvs1) }