Safe Haskell  None 

Language  Haskell2010 
This module is currently under heavy development, and no promises are made about API stability. Use with care.
We welcome any feedback / contributions on this, as it is the main point of the library.
Synopsis
 type Transform = TransformT Identity
 newtype TransformT m a = TransformT {
 unTransformT :: RWST () [String] (Anns, Int) m a
 hoistTransform :: (forall x. m x > n x) > TransformT m a > TransformT n a
 runTransform :: Anns > Transform a > (a, (Anns, Int), [String])
 runTransformT :: Anns > TransformT m a > m (a, (Anns, Int), [String])
 runTransformFrom :: Int > Anns > Transform a > (a, (Anns, Int), [String])
 runTransformFromT :: Int > Anns > TransformT m a > m (a, (Anns, Int), [String])
 logTr :: Monad m => String > TransformT m ()
 logDataWithAnnsTr :: Monad m => Data a => String > a > TransformT m ()
 getAnnsT :: Monad m => TransformT m Anns
 putAnnsT :: Monad m => Anns > TransformT m ()
 modifyAnnsT :: Monad m => (Anns > Anns) > TransformT m ()
 uniqueSrcSpanT :: Monad m => TransformT m SrcSpan
 cloneT :: (Data a, Monad m) => a > TransformT m (a, [(SrcSpan, SrcSpan)])
 graftT :: (Data a, Monad m) => Anns > a > TransformT m a
 getEntryDPT :: (Constraints a, Monad m) => a > TransformT m DeltaPos
 setEntryDPT :: (Constraints a, Monad m) => a > DeltaPos > TransformT m ()
 transferEntryDPT :: (Data a, Data b, Monad m) => Located a > Located b > TransformT m ()
 setPrecedingLinesDeclT :: Monad m => LHsDecl GhcPs > Int > Int > TransformT m ()
 setPrecedingLinesT :: (Data a, Monad m) => Located a > Int > Int > TransformT m ()
 addSimpleAnnT :: (Constraints a, Monad m) => a > DeltaPos > [(KeywordId, DeltaPos)] > TransformT m ()
 addTrailingCommaT :: (Data a, Monad m) => Located a > TransformT m ()
 removeTrailingCommaT :: (Data a, Monad m) => Located a > TransformT m ()
 class Monad m => HasTransform m where
 class Data t => HasDecls t where
 hsDecls :: Monad m => t > TransformT m [LHsDecl GhcPs]
 replaceDecls :: Monad m => t > [LHsDecl GhcPs] > TransformT m t
 hasDeclsSybTransform :: (Data t2, Monad m) => (forall t. HasDecls t => t > m t) > (LHsBind GhcPs > m (LHsBind GhcPs)) > t2 > m t2
 hsDeclsGeneric :: (Data t, Monad m) => t > TransformT m [LHsDecl GhcPs]
 hsDeclsPatBind :: Monad m => LHsBind GhcPs > TransformT m [LHsDecl GhcPs]
 hsDeclsPatBindD :: Monad m => LHsDecl GhcPs > TransformT m [LHsDecl GhcPs]
 replaceDeclsPatBind :: Monad m => LHsBind GhcPs > [LHsDecl GhcPs] > TransformT m (LHsBind GhcPs)
 replaceDeclsPatBindD :: Monad m => LHsDecl GhcPs > [LHsDecl GhcPs] > TransformT m (LHsDecl GhcPs)
 modifyDeclsT :: (HasDecls t, HasTransform m) => ([LHsDecl GhcPs] > m [LHsDecl GhcPs]) > t > m t
 modifyValD :: forall m t. HasTransform m => SrcSpan > Decl > (Match > [Decl] > m ([Decl], Maybe t)) > m (Decl, Maybe t)
 hsDeclsValBinds :: Monad m => HsLocalBinds GhcPs > TransformT m [LHsDecl GhcPs]
 replaceDeclsValbinds :: Monad m => HsLocalBinds GhcPs > [LHsDecl GhcPs] > TransformT m (HsLocalBinds GhcPs)
 insertAtStart :: HasDecls (Located ast) => Located ast > LHsDecl GhcPs > Transform (Located ast)
 insertAtEnd :: HasDecls (Located ast) => Located ast > LHsDecl GhcPs > Transform (Located ast)
 insertAfter :: HasDecls (Located ast) => Located old > Located ast > LHsDecl GhcPs > Transform (Located ast)
 insertBefore :: HasDecls (Located ast) => Located old > Located ast > LHsDecl GhcPs > Transform (Located ast)
 balanceComments :: (Data a, Data b, Monad m) => Located a > Located b > TransformT m ()
 balanceTrailingComments :: Monad m => (Data a, Data b) => Located a > Located b > TransformT m [(Comment, DeltaPos)]
 moveTrailingComments :: (Data a, Data b) => Located a > Located b > Transform ()
 captureOrder :: Data a => Located a > [Located b] > Anns > Anns
 captureOrderAnnKey :: AnnKey > [Located b] > Anns > Anns
 isUniqueSrcSpan :: SrcSpan > Bool
 mergeAnns :: Anns > Anns > Anns
 mergeAnnList :: [Anns] > Anns
 setPrecedingLinesDecl :: LHsDecl GhcPs > Int > Int > Anns > Anns
 setPrecedingLines :: Data a => Located a > Int > Int > Anns > Anns
 getEntryDP :: Constraints a => Anns > a > DeltaPos
 setEntryDP :: Constraints a => a > DeltaPos > Anns > Anns
 transferEntryDP :: (Data a, Data b) => Located a > Located b > Anns > Anns
 addTrailingComma :: Data a => Located a > DeltaPos > Anns > Anns
 wrapSig :: LSig GhcPs > LHsDecl GhcPs
 wrapDecl :: LHsBind GhcPs > LHsDecl GhcPs
 decl2Sig :: LHsDecl name > [LSig name]
 decl2Bind :: LHsDecl name > [LHsBind name]
The Transform Monad
type Transform = TransformT Identity Source #
Monad type for updating the AST and managing the annotations at the same time. The W state is used to generate logging information if required.
newtype TransformT m a Source #
Monad transformer version of Transform
monad
TransformT  

Instances
hoistTransform :: (forall x. m x > n x) > TransformT m a > TransformT n a Source #
Change inner monad of TransformT
.
runTransformT :: Anns > TransformT m a > m (a, (Anns, Int), [String]) Source #
runTransformFromT :: Int > Anns > TransformT m a > m (a, (Anns, Int), [String]) Source #
Run a monad transformer stack for the TransformT
monad transformer
Transform monad operations
logDataWithAnnsTr :: Monad m => Data a => String > a > TransformT m () Source #
Log a representation of the given AST with annotations to the output of the Monad
getAnnsT :: Monad m => TransformT m Anns Source #
Access the Anns
being modified in this transformation
modifyAnnsT :: Monad m => (Anns > Anns) > TransformT m () Source #
Change the stored Anns
uniqueSrcSpanT :: Monad m => TransformT m SrcSpan Source #
cloneT :: (Data a, Monad m) => a > TransformT m (a, [(SrcSpan, SrcSpan)]) Source #
Make a copy of an AST element, replacing the existing SrcSpans with new ones, and duplicating the matching annotations.
graftT :: (Data a, Monad m) => Anns > a > TransformT m a Source #
Slightly more general form of cloneT
getEntryDPT :: (Constraints a, Monad m) => a > TransformT m DeltaPos Source #
Transform
monad version of getEntryDP
setEntryDPT :: (Constraints a, Monad m) => a > DeltaPos > TransformT m () Source #
Transform
monad version of getEntryDP
transferEntryDPT :: (Data a, Data b, Monad m) => Located a > Located b > TransformT m () Source #
Transform
monad version of transferEntryDP
setPrecedingLinesDeclT :: Monad m => LHsDecl GhcPs > Int > Int > TransformT m () Source #
Transform
monad version of setPrecedingLinesDecl
setPrecedingLinesT :: (Data a, Monad m) => Located a > Int > Int > TransformT m () Source #
Transform
monad version of setPrecedingLines
addSimpleAnnT :: (Constraints a, Monad m) => a > DeltaPos > [(KeywordId, DeltaPos)] > TransformT m () Source #
Create a simple Annotation
without comments, and attach it to the first
parameter.
addTrailingCommaT :: (Data a, Monad m) => Located a > TransformT m () Source #
Add a trailing comma annotation, unless there is already one
removeTrailingCommaT :: (Data a, Monad m) => Located a > TransformT m () Source #
Remove a trailing comma annotation, if there is one one
Managing declarations, in Transform monad
class Monad m => HasTransform m where Source #
Used to integrate a Transform
into other Monad stacks
Instances
Monad m => HasTransform (TransformT m) Source #  
Defined in Language.Haskell.GHC.ExactPrint.Transform liftT :: Transform a > TransformT m a Source # 
class Data t => HasDecls t where Source #
Provide a means to get and process the immediate child declartions of a given AST element.
hsDecls :: Monad m => t > TransformT m [LHsDecl GhcPs] Source #
Return the HsDecl
s that are directly enclosed in the
given syntax phrase. They are always returned in the wrapped HsDecl
form, even if orginating in local decls. This is safe, as annotations
never attach to the wrapper, only to the wrapped item.
replaceDecls :: Monad m => t > [LHsDecl GhcPs] > TransformT m t Source #
Replace the directly enclosed decl list by the given
decl list. Runs in the Transform
monad to be able to update list order
annotations, and rebalance comments and other layout changes as needed.
For example, a call on replaceDecls for a wrapped FunBind
having no
where clause will convert
 This is a function foo = x  comment1
in to
 This is a function foo = x  comment1 where nn = 2
Instances
HasDecls ParsedSource Source #  
Defined in Language.Haskell.GHC.ExactPrint.Transform hsDecls :: forall (m :: Type > Type). Monad m => ParsedSource > TransformT m [LHsDecl GhcPs] Source # replaceDecls :: forall (m :: Type > Type). Monad m => ParsedSource > [LHsDecl GhcPs] > TransformT m ParsedSource Source #  
HasDecls (LHsExpr GhcPs) Source #  
HasDecls (LMatch GhcPs (LHsExpr GhcPs)) Source #  
Defined in Language.Haskell.GHC.ExactPrint.Transform  
HasDecls (LStmt GhcPs (LHsExpr GhcPs)) Source #  
Defined in Language.Haskell.GHC.ExactPrint.Transform 
:: (Data t2, Monad m)  
=> (forall t. HasDecls t => t > m t)  Worker function for the general case 
> (LHsBind GhcPs > m (LHsBind GhcPs))  Worker function for FunBind/PatBind 
> t2  Item to be updated 
> m t2 
Do a transformation on an AST fragment by providing a function to process
the general case and one specific for a LHsBind
. This is required
because a FunBind
may have multiple Match
items, so we cannot
gurantee that replaceDecls
after hsDecls
is idempotent.
hsDeclsGeneric :: (Data t, Monad m) => t > TransformT m [LHsDecl GhcPs] Source #
hsDeclsPatBind :: Monad m => LHsBind GhcPs > TransformT m [LHsDecl GhcPs] Source #
Extract the immediate declarations for a PatBind
. This
cannot be a member of HasDecls
because a FunBind
is not idempotent
for hsDecls
/ replaceDecls
. hsDeclsPatBind
/ replaceDeclsPatBind
is
idempotent.
hsDeclsPatBindD :: Monad m => LHsDecl GhcPs > TransformT m [LHsDecl GhcPs] Source #
Extract the immediate declarations for a PatBind
wrapped in a ValD
. This
cannot be a member of HasDecls
because a FunBind
is not idempotent
for hsDecls
/ replaceDecls
. hsDeclsPatBindD
/ replaceDeclsPatBindD
is
idempotent.
replaceDeclsPatBind :: Monad m => LHsBind GhcPs > [LHsDecl GhcPs] > TransformT m (LHsBind GhcPs) Source #
Replace the immediate declarations for a PatBind
. This
cannot be a member of HasDecls
because a FunBind
is not idempotent
for hsDecls
/ replaceDecls
. hsDeclsPatBind
/ replaceDeclsPatBind
is
idempotent.
replaceDeclsPatBindD :: Monad m => LHsDecl GhcPs > [LHsDecl GhcPs] > TransformT m (LHsDecl GhcPs) Source #
Replace the immediate declarations for a PatBind
wrapped in a ValD
. This
cannot be a member of HasDecls
because a FunBind
is not idempotent
for hsDecls
/ replaceDecls
. hsDeclsPatBindD
/ replaceDeclsPatBindD
is
idempotent.
modifyDeclsT :: (HasDecls t, HasTransform m) => ([LHsDecl GhcPs] > m [LHsDecl GhcPs]) > t > m t Source #
Apply a transformation to the decls contained in t
modifyValD :: forall m t. HasTransform m => SrcSpan > Decl > (Match > [Decl] > m ([Decl], Maybe t)) > m (Decl, Maybe t) Source #
Utility, does not manage layout
hsDeclsValBinds :: Monad m => HsLocalBinds GhcPs > TransformT m [LHsDecl GhcPs] Source #
Utility function for extracting decls from HsLocalBinds
. Use with
care, as this does not necessarily return the declarations in order, the
ordering should be done by the calling function from the HsLocalBinds
context in the AST.
replaceDeclsValbinds :: Monad m => HsLocalBinds GhcPs > [LHsDecl GhcPs] > TransformT m (HsLocalBinds GhcPs) Source #
Utility function for returning decls to HsLocalBinds
. Use with
care, as this does not manage the declaration order, the
ordering should be done by the calling function from the HsLocalBinds
context in the AST.
Managing lists, Transform monad
insertAtStart :: HasDecls (Located ast) => Located ast > LHsDecl GhcPs > Transform (Located ast) Source #
Insert a declaration at the beginning or end of the subdecls of the given AST item
insertAtEnd :: HasDecls (Located ast) => Located ast > LHsDecl GhcPs > Transform (Located ast) Source #
Insert a declaration at the beginning or end of the subdecls of the given AST item
insertAfter :: HasDecls (Located ast) => Located old > Located ast > LHsDecl GhcPs > Transform (Located ast) Source #
Insert a declaration at a specific location in the subdecls of the given AST item
insertBefore :: HasDecls (Located ast) => Located old > Located ast > LHsDecl GhcPs > Transform (Located ast) Source #
Insert a declaration at a specific location in the subdecls of the given AST item
Low level operations used in HasDecls
balanceComments :: (Data a, Data b, Monad m) => Located a > Located b > TransformT m () Source #
The relatavise phase puts all comments appearing between the end of one AST
item and the beginning of the next as annPriorComments
for the second one.
This function takes two adjacent AST items and moves any annPriorComments
from the second one to the annFollowingComments
of the first if they belong
to it instead. This is typically required before deleting or duplicating
either of the AST elements.
balanceTrailingComments :: Monad m => (Data a, Data b) => Located a > Located b > TransformT m [(Comment, DeltaPos)] Source #
After moving an AST element, make sure any comments that may belong with the following element in fact do. Of necessity this is a heuristic process, to be tuned later. Possibly a variant should be provided with a passedin decision function.
moveTrailingComments :: (Data a, Data b) => Located a > Located b > Transform () Source #
Move any annFollowingComments
values from the Annotation
associated to
the first parameter to that of the second.
Managing lists, pure functions
captureOrder :: Data a => Located a > [Located b] > Anns > Anns Source #
If a list has been reordered or had items added, capture the new order in
the appropriate annSortKey
attached to the Annotation
for the first
parameter.
captureOrderAnnKey :: AnnKey > [Located b] > Anns > Anns Source #
If a list has been reordered or had items added, capture the new order in
the appropriate annSortKey
item of the supplied AnnKey
Operations
isUniqueSrcSpan :: SrcSpan > Bool Source #
Test whether a given SrcSpan
was generated by uniqueSrcSpanT
Pure functions
mergeAnnList :: [Anns] > Anns Source #
Combine a list of annotations
setPrecedingLinesDecl :: LHsDecl GhcPs > Int > Int > Anns > Anns Source #
Unwrap a HsDecl and call setPrecedingLines on it ++AZ++ TODO: get rid of this, it is a synonym only
setPrecedingLines :: Data a => Located a > Int > Int > Anns > Anns Source #
Adjust the entry annotations to provide an n
line preceding gap
getEntryDP :: Constraints a => Anns > a > DeltaPos Source #
setEntryDP :: Constraints a => a > DeltaPos > Anns > Anns Source #
transferEntryDP :: (Data a, Data b) => Located a > Located b > Anns > Anns Source #
Take the annEntryDelta associated with the first item and associate it with the second. Also transfer any comments occuring before it.