Reorganisation of the source tree

[ghc-hetmet.git] / compiler / hsSyn / HsSyn.lhs

diff --git a/compiler/hsSyn/HsSyn.lhs b/compiler/hsSyn/HsSyn.lhs
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+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
+%
+\section{Haskell abstract syntax definition}
+
+This module glues together the pieces of the Haskell abstract syntax,
+which is declared in the various \tr{Hs*} modules.  This module,
+therefore, is almost nothing but re-exporting.
+
+\begin{code}
+module HsSyn (
+       module HsBinds,
+       module HsDecls,
+       module HsExpr,
+       module HsImpExp,
+       module HsLit,
+       module HsPat,
+       module HsTypes,
+       module HsUtils,
+       Fixity,
+
+       HsModule(..), HsExtCore(..)
+     ) where
+
+#include "HsVersions.h"
+
+-- friends:
+import HsDecls         
+import HsBinds
+import HsExpr
+import HsImpExp
+import HsLit
+import HsPat
+import HsTypes
+import HscTypes                ( DeprecTxt )
+import BasicTypes      ( Fixity )
+import HsUtils
+
+-- others:
+import IfaceSyn                ( IfaceBinding )
+import Outputable
+import SrcLoc          ( Located(..) )
+import Module          ( Module )
+\end{code}
+
+All we actually declare here is the top-level structure for a module.
+\begin{code}
+data HsModule name
+  = HsModule
+       (Maybe (Located Module))-- Nothing => "module X where" is omitted
+                               --      (in which case the next field is Nothing too)
+       (Maybe [LIE name])      -- Export list; Nothing => export list omitted, so export everything
+                               -- Just [] => export *nothing*
+                               -- Just [...] => as you would expect...
+       [LImportDecl name]      -- We snaffle interesting stuff out of the
+                               -- imported interfaces early on, adding that
+                               -- info to TyDecls/etc; so this list is
+                               -- often empty, downstream.
+       [LHsDecl name]          -- Type, class, value, and interface signature decls
+       (Maybe DeprecTxt)       -- reason/explanation for deprecation of this module
+
+data HsExtCore name    -- Read from Foo.hcr
+  = HsExtCore
+       Module
+       [TyClDecl name] -- Type declarations only; just as in Haskell source,
+                       -- so that we can infer kinds etc
+       [IfaceBinding]  -- And the bindings
+\end{code}
+
+\begin{code}
+instance (OutputableBndr name)
+       => Outputable (HsModule name) where
+
+    ppr (HsModule Nothing _ imports decls _)
+      = pp_nonnull imports $$ pp_nonnull decls
+
+    ppr (HsModule (Just name) exports imports decls deprec)
+      = vcat [
+           case exports of
+             Nothing -> pp_header (ptext SLIT("where"))
+             Just es -> vcat [
+                          pp_header lparen,
+                          nest 8 (fsep (punctuate comma (map ppr es))),
+                          nest 4 (ptext SLIT(") where"))
+                         ],
+           pp_nonnull imports,
+           pp_nonnull decls
+       ]
+      where
+       pp_header rest = case deprec of
+           Nothing -> pp_modname <+> rest
+           Just d -> vcat [ pp_modname, ppr d, rest ]
+
+       pp_modname = ptext SLIT("module") <+> ppr name
+
+pp_nonnull [] = empty
+pp_nonnull xs = vcat (map ppr xs)
+\end{code}