Documentation

lookupInfoOccRn is intended for use in GHCi's ":info" command It finds all the GREs that RdrName could mean, not complaining about ambiguity, but rather returning them all (c.f. #9881).

lookupInfoOccRn is also used in situations where we check for at least one definition of the RdrName, not complaining about multiple definitions (see #17832).

Look up a RdrName used as a variable in an expression.

This may be a local variable, global variable, or one or more record selector functions. It will not return record fields created with the NoFieldSelectors extension (see Note [NoFieldSelectors]).

If the name is not in scope at the term level, but its promoted equivalent is in scope at the type level, the lookup will succeed (so that the type-checker can report a more informative error later). See Note [Promotion].

Look up an occurrence of a field in record construction or pattern matching (but not update).

If -XDisambiguateRecordFields is off, then we will pass Nothing for the DataCon Name, i.e. we don't use the data constructor for disambiguation. See Note [DisambiguateRecordFields] and Note [NoFieldSelectors].

Returns all possible collections of field labels for the given record update.

Example:

data D = MkD { fld1 :: Int, fld2 :: Bool } data E = MkE1 { fld1 :: Int, fld2 :: Bool, fld3 :: Char } | MkE2 { fld1 :: Int, fld2 :: Bool } data F = MkF1 { fld1 :: Int } | MkF2 { fld2 :: Bool }

f r = r { fld1 = a, fld2 = b }

This function will return:

[ D.fld1, D.fld2

-- could be a record update at type D , [ E.fld1, E.fld2 ] -- could be a record update at type E ] -- cannot be a record update at type F: no constructor has both -- of the fields fld1 and fld2

If there are no valid parents for the record update, throws a TcRnBadRecordUpdate error.

Used in export lists to lookup the children.

Lookup a name in relation to the names in a HsSigCtxt

Look up the arity and record fields of a constructor.

Look up the GREInfo associated with the given Name by looking up in the type environment.

Whether to report deprecation warnings when registering a used GRE

There is no option to only emit declaration warnings since everywhere we emit the declaration warnings we also emit export warnings (See Note [Handling of deprecations] for details)