\section[Name]{@Name@: to transmit name info from renamer to typechecker}
\begin{code}
-module Name (
- -- Re-export the OccName stuff
- module OccName,
+-- |
+-- #name_types#
+-- GHC uses several kinds of name internally:
+--
+-- * 'OccName.OccName': see "OccName#name_types"
+--
+-- * 'RdrName.RdrName': see "RdrName#name_types"
+--
+-- * 'Name.Name' is the type of names that have had their scoping and binding resolved. They
+-- have an 'OccName.OccName' but also a 'Unique.Unique' that disambiguates Names that have
+-- the same 'OccName.OccName' and indeed is used for all 'Name.Name' comparison. Names
+-- also contain information about where they originated from, see "Name#name_sorts"
+--
+-- * 'Id.Id': see "Id#name_types"
+--
+-- * 'Var.Var': see "Var#name_types"
+--
+-- #name_sorts#
+-- Names are one of:
+--
+-- * External, if they name things declared in other modules. Some external
+-- Names are wired in, i.e. they name primitives defined in the compiler itself
+--
+-- * Internal, if they name things in the module being compiled. Some internal
+-- Names are system names, if they are names manufactured by the compiler
- -- The Name type
+module Name (
+ -- * The main types
Name, -- Abstract
- BuiltInSyntax(..),
+ BuiltInSyntax(..),
+
+ -- ** Creating 'Name's
mkInternalName, mkSystemName,
mkSystemVarName, mkSysTvName,
mkFCallName, mkIPName,
mkTickBoxOpName,
mkExternalName, mkWiredInName,
+ -- ** Manipulating and deconstructing 'Name's
nameUnique, setNameUnique,
nameOccName, nameModule, nameModule_maybe,
tidyNameOcc,
nameSrcLoc, nameSrcSpan, pprNameLoc,
+ -- ** Predicates on 'Name's
isSystemName, isInternalName, isExternalName,
- isTyVarName, isTyConName, isWiredInName, isBuiltInSyntax,
+ isTyVarName, isTyConName, isDataConName,
+ isValName, isVarName,
+ isWiredInName, isBuiltInSyntax,
wiredInNameTyThing_maybe,
nameIsLocalOrFrom,
-
- -- Class NamedThing and overloaded friends
+
+ -- * Class 'NamedThing' and overloaded friends
NamedThing(..),
getSrcLoc, getSrcSpan, getOccString,
- pprInfixName, pprPrefixName
+
+ pprInfixName, pprPrefixName,
+
+ -- Re-export the OccName stuff
+ module OccName
) where
import {-# SOURCE #-} TypeRep( TyThing )
import Unique
import Maybes
import Binary
+import StaticFlags
import FastTypes
import FastString
import Outputable
%************************************************************************
\begin{code}
+-- | A unique, unambigious name for something, containing information about where
+-- that thing originated.
data Name = Name {
n_sort :: NameSort, -- What sort of name it is
n_occ :: !OccName, -- Its occurrence name
| System -- A system-defined Id or TyVar. Typically the
-- OccName is very uninformative (like 's')
-data BuiltInSyntax = BuiltInSyntax | UserSyntax
--- BuiltInSyntax is for things like (:), [], tuples etc,
--- which have special syntactic forms. They aren't "in scope"
+-- | BuiltInSyntax is for things like @(:)@, @[]@ and tuples,
+-- which have special syntactic forms. They aren't in scope
-- as such.
+data BuiltInSyntax = BuiltInSyntax | UserSyntax
\end{code}
Notes about the NameSorts:
nameSrcSpan name = n_loc name
\end{code}
+%************************************************************************
+%* *
+\subsection{Predicates on names}
+%* *
+%************************************************************************
+
\begin{code}
nameIsLocalOrFrom :: Module -> Name -> Bool
isInternalName :: Name -> Bool
isTyConName :: Name -> Bool
isTyConName name = isTcOcc (nameOccName name)
+isDataConName :: Name -> Bool
+isDataConName name = isDataOcc (nameOccName name)
+
+isValName :: Name -> Bool
+isValName name = isValOcc (nameOccName name)
+
+isVarName :: Name -> Bool
+isVarName = isVarOcc . nameOccName
+
isSystemName (Name {n_sort = System}) = True
isSystemName _ = False
\end{code}
%************************************************************************
\begin{code}
+-- | Create a name which is (for now at least) local to the current module and hence
+-- does not need a 'Module' to disambiguate it from other 'Name's
mkInternalName :: Unique -> OccName -> SrcSpan -> Name
mkInternalName uniq occ loc = Name { n_uniq = getKeyFastInt uniq, n_sort = Internal, n_occ = occ, n_loc = loc }
-- NB: You might worry that after lots of huffing and
-- * for interface files we tidyCore first, which puts the uniques
-- into the print name (see setNameVisibility below)
+-- | Create a name which definitely originates in the given module
mkExternalName :: Unique -> Module -> OccName -> SrcSpan -> Name
mkExternalName uniq mod occ loc
= Name { n_uniq = getKeyFastInt uniq, n_sort = External mod,
n_occ = occ, n_loc = loc }
-mkWiredInName :: Module -> OccName -> Unique -> TyThing -> BuiltInSyntax
- -> Name
+-- | Create a name which is actually defined by the compiler itself
+mkWiredInName :: Module -> OccName -> Unique -> TyThing -> BuiltInSyntax -> Name
mkWiredInName mod occ uniq thing built_in
= Name { n_uniq = getKeyFastInt uniq,
n_sort = WiredIn mod thing built_in,
n_occ = occ, n_loc = wiredInSrcSpan }
+-- | Create a name brought into being by the compiler
mkSystemName :: Unique -> OccName -> Name
mkSystemName uniq occ = Name { n_uniq = getKeyFastInt uniq, n_sort = System,
n_occ = occ, n_loc = noSrcSpan }
mkSysTvName :: Unique -> FastString -> Name
mkSysTvName uniq fs = mkSystemName uniq (mkOccNameFS tvName fs)
+-- | Make a name for a foreign call
mkFCallName :: Unique -> String -> Name
-- The encoded string completely describes the ccall
mkFCallName uniq str = Name { n_uniq = getKeyFastInt uniq, n_sort = Internal,
n_occ = mkVarOcc str, n_loc = noSrcSpan }
+
mkTickBoxOpName :: Unique -> String -> Name
mkTickBoxOpName uniq str
= Name { n_uniq = getKeyFastInt uniq, n_sort = Internal,
n_occ = mkVarOcc str, n_loc = noSrcSpan }
+-- | Make the name of an implicit parameter
mkIPName :: Unique -> OccName -> Name
mkIPName uniq occ
= Name { n_uniq = getKeyFastInt uniq,
tidyNameOcc name@(Name { n_sort = System }) occ = name { n_occ = occ, n_sort = Internal}
tidyNameOcc name occ = name { n_occ = occ }
+-- | Make the 'Name' into an internal name, regardless of what it was to begin with
localiseName :: Name -> Name
localiseName n = n { n_sort = Internal }
\end{code}
-
%************************************************************************
%* *
-\subsection{Predicates and selectors}
+\subsection{Hashing and comparison}
%* *
%************************************************************************
-- The +1 avoids keys with lots of zeros in the ls bits, which
-- interacts badly with the cheap and cheerful multiplication in
-- hashExpr
-\end{code}
+cmpName :: Name -> Name -> Ordering
+cmpName n1 n2 = iBox (n_uniq n1) `compare` iBox (n_uniq n2)
+\end{code}
%************************************************************************
%* *
%************************************************************************
\begin{code}
-cmpName :: Name -> Name -> Ordering
-cmpName n1 n2 = iBox (n_uniq n1) `compare` iBox (n_uniq n2)
-\end{code}
-
-\begin{code}
instance Eq Name where
a == b = case (a `compare` b) of { EQ -> True; _ -> False }
a /= b = case (a `compare` b) of { EQ -> False; _ -> True }
| codeStyle sty = pprUnique uniq
| debugStyle sty = ppr_occ_name occ <> braces (hsep [pprNameSpaceBrief (occNameSpace occ),
pprUnique uniq])
- | dumpStyle sty = ppr_occ_name occ <> char '_' <> pprUnique uniq
+ | dumpStyle sty = ppr_occ_name occ <> ppr_underscore_unique uniq
-- For debug dumps, we're not necessarily dumping
-- tidied code, so we need to print the uniques.
| otherwise = ppr_occ_name occ -- User style
pprSystem :: PprStyle -> Unique -> OccName -> SDoc
pprSystem sty uniq occ
| codeStyle sty = pprUnique uniq
- | debugStyle sty = ppr_occ_name occ <> char '_' <> pprUnique uniq
+ | debugStyle sty = ppr_occ_name occ <> ppr_underscore_unique uniq
<> braces (pprNameSpaceBrief (occNameSpace occ))
- | otherwise = ppr_occ_name occ <> char '_' <> pprUnique uniq
+ | otherwise = ppr_occ_name occ <> ppr_underscore_unique uniq
-- If the tidy phase hasn't run, the OccName
-- is unlikely to be informative (like 's'),
-- so print the unique
+ppr_underscore_unique :: Unique -> SDoc
+-- Print an underscore separating the name from its unique
+-- But suppress it if we aren't printing the uniques anyway
+ppr_underscore_unique uniq
+ | opt_SuppressUniques = empty
+ | otherwise = char '_' <> pprUnique uniq
+
ppr_occ_name :: OccName -> SDoc
ppr_occ_name occ = ftext (occNameFS occ)
-- Don't use pprOccName; instead, just print the string of the OccName;
%************************************************************************
\begin{code}
+-- | A class allowing convenient access to the 'Name' of various datatypes
class NamedThing a where
getOccName :: a -> OccName
getName :: a -> Name