Reorganisation of the source tree

Most of the other users of the fptools build system have migrated to
Cabal, and with the move to darcs we can now flatten the source tree
without losing history, so here goes.

The main change is that the ghc/ subdir is gone, and most of what it
contained is now at the top level.  The build system now makes no
pretense at being multi-project, it is just the GHC build system.

No doubt this will break many things, and there will be a period of
instability while we fix the dependencies.  A straightforward build
should work, but I haven't yet fixed binary/source distributions.
Changes to the Building Guide will follow, too.

1 files changed, 125 insertions, 0 deletions

diff --git a/compiler/hsSyn/HsImpExp.lhs b/compiler/hsSyn/HsImpExp.lhs
new file mode 100644
index 0000000000..220afb7499
--- /dev/null
+++ b/compiler/hsSyn/HsImpExp.lhs
@@ -0,0 +1,125 @@
+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
+%
+\section[HsImpExp]{Abstract syntax: imports, exports, interfaces}
+
+\begin{code}
+module HsImpExp where
+
+#include "HsVersions.h"
+
+import Module		( Module )
+import Outputable
+import FastString
+import SrcLoc		( Located(..) )
+import Char		( isAlpha )
+\end{code}
+
+%************************************************************************
+%*									*
+\subsection{Import and export declaration lists}
+%*									*
+%************************************************************************
+
+One per \tr{import} declaration in a module.
+\begin{code}
+type LImportDecl name = Located (ImportDecl name)
+
+data ImportDecl name
+  = ImportDecl	  (Located Module)		-- module name
+		  Bool				-- True <=> {-# SOURCE #-} import
+		  Bool				-- True => qualified
+		  (Maybe Module)		-- as Module
+		  (Maybe (Bool, [LIE name]))	-- (True => hiding, names)
+\end{code}
+
+\begin{code}
+instance (Outputable name) => Outputable (ImportDecl name) where
+    ppr (ImportDecl mod from qual as spec)
+      = hang (hsep [ptext SLIT("import"), ppr_imp from, 
+                    pp_qual qual, ppr mod, pp_as as])
+	     4 (pp_spec spec)
+      where
+	pp_qual False   = empty
+	pp_qual True	= ptext SLIT("qualified")
+
+	pp_as Nothing   = empty
+	pp_as (Just a)  = ptext SLIT("as ") <+> ppr a
+
+	ppr_imp True  = ptext SLIT("{-# SOURCE #-}")
+	ppr_imp False = empty
+
+	pp_spec Nothing = empty
+	pp_spec (Just (False, spec))
+			= parens (interpp'SP spec)
+	pp_spec (Just (True, spec))
+			= ptext SLIT("hiding") <+> parens (interpp'SP spec)
+
+ideclName (ImportDecl mod_nm _ _ _ _) = mod_nm
+\end{code}
+
+%************************************************************************
+%*									*
+\subsection{Imported and exported entities}
+%*									*
+%************************************************************************
+
+\begin{code}
+type LIE name = Located (IE name)
+
+data IE name
+  = IEVar		name
+  | IEThingAbs          name		-- Class/Type (can't tell)
+  | IEThingAll          name		-- Class/Type plus all methods/constructors
+  | IEThingWith		name [name]	-- Class/Type plus some methods/constructors
+  | IEModuleContents    Module		-- (Export Only)
+\end{code}
+
+\begin{code}
+ieName :: IE name -> name
+ieName (IEVar n) 	 = n
+ieName (IEThingAbs  n)   = n
+ieName (IEThingWith n _) = n
+ieName (IEThingAll  n)   = n
+
+ieNames :: IE a -> [a]
+ieNames (IEVar            n   ) = [n]
+ieNames (IEThingAbs       n   ) = [n]
+ieNames (IEThingAll       n   ) = [n]
+ieNames (IEThingWith      n ns) = n:ns
+ieNames (IEModuleContents _   ) = []
+\end{code}
+
+\begin{code}
+instance (Outputable name) => Outputable (IE name) where
+    ppr (IEVar	        var)	= pprHsVar var
+    ppr (IEThingAbs	thing)	= ppr thing
+    ppr (IEThingAll	thing)	= hcat [ppr thing, text "(..)"]
+    ppr (IEThingWith thing withs)
+	= ppr thing <> parens (fsep (punctuate comma (map pprHsVar withs)))
+    ppr (IEModuleContents mod)
+	= ptext SLIT("module") <+> ppr mod
+\end{code}
+
+\begin{code}
+pprHsVar :: Outputable name => name -> SDoc
+pprHsVar v | isOperator ppr_v = parens ppr_v
+	   | otherwise	      = ppr_v
+	   where
+	     ppr_v = ppr v
+
+isOperator :: SDoc -> Bool
+isOperator ppr_v 
+  = case showSDocUnqual ppr_v of
+	('(':s)   -> False		-- (), (,) etc
+	('[':s)   -> False		-- []
+	('$':c:s) -> not (isAlpha c)	-- Don't treat $d as an operator
+	(':':c:s) -> not (isAlpha c)	-- Don't treat :T as an operator
+	('_':s)   -> False		-- Not an operator
+	(c:s)     -> not (isAlpha c)	-- Starts with non-alpha
+	other     -> False
+    -- We use (showSDoc (ppr v)), rather than isSymOcc (getOccName v) simply so
+    -- that we don't need NamedThing in the context of all these functions.
+    -- Gruesome, but simple.
+\end{code}
+