-- friends:
import HsDecls ( HsGroup )
import HsBinds ( HsBinds(..), nullBinds )
-import HsPat ( Pat )
-import HsLit ( HsLit, HsOverLit )
-import HsTypes ( HsType, PostTcType, SyntaxName )
+import HsPat ( Pat(..), HsConDetails(..) )
+import HsLit ( HsLit(..), HsOverLit )
+import HsTypes ( HsType, PostTcType, SyntaxName, placeHolderType )
import HsImpExp ( isOperator, pprHsVar )
-- others:
-import ForeignCall ( Safety )
-import PprType ( pprParendType )
-import Type ( Type )
+import Type ( Type, pprParendType )
import Var ( TyVar, Id )
import Name ( Name )
-import NameSet ( FreeVars )
import DataCon ( DataCon )
-import CStrings ( CLabelString, pprCLabelString )
import BasicTypes ( IPName, Boxity, tupleParens, Fixity(..) )
-import SrcLoc ( SrcLoc )
+import SrcLoc ( SrcLoc, generatedSrcLoc )
import Outputable
import FastString
\end{code}
+
+%************************************************************************
+%* *
+ Some useful helpers for constructing expressions
+%* *
+%************************************************************************
+
+\begin{code}
+mkHsApps f xs = foldl HsApp (HsVar f) xs
+mkHsVarApps f xs = foldl HsApp (HsVar f) (map HsVar xs)
+
+mkHsIntLit n = HsLit (HsInt n)
+mkHsString s = HsString (mkFastString s)
+
+mkConPat con vars = ConPatIn con (PrefixCon (map VarPat vars))
+mkNullaryConPat con = ConPatIn con (PrefixCon [])
+
+mkSimpleHsAlt :: Pat id -> HsExpr id -> Match id
+-- A simple lambda with a single pattern, no binds, no guards; pre-typechecking
+mkSimpleHsAlt pat expr
+ = mkSimpleMatch [pat] expr placeHolderType generatedSrcLoc
+
+mkSimpleMatch :: [Pat id] -> HsExpr id -> Type -> SrcLoc -> Match id
+mkSimpleMatch pats rhs rhs_ty locn
+ = Match pats Nothing (GRHSs (unguardedRHS rhs locn) EmptyBinds rhs_ty)
+
+unguardedRHS :: HsExpr id -> SrcLoc -> [GRHS id]
+unguardedRHS rhs loc = [GRHS [ResultStmt rhs loc] loc]
+
+glueBindsOnGRHSs :: HsBinds id -> GRHSs id -> GRHSs id
+glueBindsOnGRHSs EmptyBinds grhss = grhss
+glueBindsOnGRHSs binds1 (GRHSs grhss binds2 ty)
+ = GRHSs grhss (binds1 `ThenBinds` binds2) ty
+\end{code}
+
+
%************************************************************************
%* *
\subsection{Expressions proper}
(HsExpr id) -- (typechecked, of course)
(ArithSeqInfo id)
- | HsCCall CLabelString -- call into the C world; string is
- [HsExpr id] -- the C function; exprs are the
- -- arguments to pass.
- Safety -- True <=> might cause Haskell
- -- garbage-collection (must generate
- -- more paranoid code)
- Bool -- True <=> it's really a "casm"
- -- NOTE: this CCall is the *boxed*
- -- version; the desugarer will convert
- -- it into the unboxed "ccall#".
- PostTcType -- The result type; will be *bottom*
- -- until the typechecker gets ahold of it
-
| HsSCC FastString -- "set cost centre" (_scc_) annotation
(HsExpr id) -- expr whose cost is to be measured
-- The id is just a unique name to
-- identify this splice point
- | HsReify (HsReify id) -- reifyType t, reifyDecl i, reifyFixity
-
-----------------------------------------------------------
-- Arrow notation extension
pp_e2 = pprParendExpr e2
pp_prefixly
- = hang (pprExpr op) 4 (sep [pp_e1, pp_e2])
+ = hang (ppr_expr op) 4 (sep [pp_e1, pp_e2])
pp_infixly v
= sep [pp_e1, hsep [pprInfix v, pp_e2]]
-- special case: let ... in let ...
ppr_expr (HsLet binds expr@(HsLet _ _))
= sep [hang (ptext SLIT("let")) 2 (hsep [pprBinds binds, ptext SLIT("in")]),
- pprExpr expr]
+ ppr_expr expr]
ppr_expr (HsLet binds expr)
= sep [hang (ptext SLIT("let")) 2 (pprBinds binds),
ppr_expr (ELazyPat e) = char '~' <> pprParendExpr e
ppr_expr (EAsPat v e) = ppr v <> char '@' <> pprParendExpr e
-ppr_expr (HsCCall fun args _ is_asm result_ty)
- = hang (if is_asm
- then ptext SLIT("_casm_ ``") <> pprCLabelString fun <> ptext SLIT("''")
- else ptext SLIT("_ccall_") <+> pprCLabelString fun)
- 4 (sep (map pprParendExpr args))
-
ppr_expr (HsSCC lbl expr)
= sep [ ptext SLIT("_scc_") <+> doubleQuotes (ftext lbl), pprParendExpr expr ]
ppr_expr (HsSplice n e _) = char '$' <> brackets (ppr n) <> pprParendExpr e
ppr_expr (HsBracket b _) = pprHsBracket b
ppr_expr (HsBracketOut e ps) = ppr e $$ ptext SLIT("where") <+> ppr ps
-ppr_expr (HsReify r) = ppr r
ppr_expr (HsProc pat (HsCmdTop cmd _ _ _) _)
= hsep [ptext SLIT("proc"), ppr pat, ptext SLIT("->"), pprExpr cmd]
ppr_expr (HsArrApp arrow arg _ HsFirstOrderApp True _)
- = hsep [pprExpr arrow, ptext SLIT("-<"), pprExpr arg]
+ = hsep [ppr_expr arrow, ptext SLIT("-<"), ppr_expr arg]
ppr_expr (HsArrApp arrow arg _ HsFirstOrderApp False _)
- = hsep [pprExpr arg, ptext SLIT(">-"), pprExpr arrow]
+ = hsep [ppr_expr arg, ptext SLIT(">-"), ppr_expr arrow]
ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp True _)
- = hsep [pprExpr arrow, ptext SLIT("-<<"), pprExpr arg]
+ = hsep [ppr_expr arrow, ptext SLIT("-<<"), ppr_expr arg]
ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp False _)
- = hsep [pprExpr arg, ptext SLIT(">>-"), pprExpr arrow]
+ = hsep [ppr_expr arg, ptext SLIT(">>-"), ppr_expr arrow]
ppr_expr (HsArrForm (HsVar v) (Just _) [arg1, arg2] _)
= sep [pprCmdArg arg1, hsep [pprInfix v, pprCmdArg arg2]]
ppr_expr (HsArrForm op _ args _)
- = hang (ptext SLIT("(|") <> pprExpr op)
+ = hang (ptext SLIT("(|") <> ppr_expr op)
4 (sep (map pprCmdArg args) <> ptext SLIT("|)"))
pprCmdArg :: OutputableBndr id => HsCmdTop id -> SDoc
-pprCmdArg (HsCmdTop cmd@(HsArrForm _ Nothing [] _) _ _ _) = pprExpr cmd
-pprCmdArg (HsCmdTop cmd _ _ _) = parens (pprExpr cmd)
+pprCmdArg (HsCmdTop cmd@(HsArrForm _ Nothing [] _) _ _ _) = ppr_expr cmd
+pprCmdArg (HsCmdTop cmd _ _ _) = parens (ppr_expr cmd)
-- Put a var in backquotes if it's not an operator already
pprInfix :: Outputable name => name -> SDoc
pprParendExpr expr
= let
- pp_as_was = pprExpr expr
+ pp_as_was = ppr_expr expr
+ -- Using ppr_expr here avoids the call to 'deeper'
+ -- Not sure if that's always right.
in
case expr of
- HsLit l -> ppr l
- HsOverLit l -> ppr l
-
- HsVar _ -> pp_as_was
- HsIPVar _ -> pp_as_was
- ExplicitList _ _ -> pp_as_was
- ExplicitPArr _ _ -> pp_as_was
- ExplicitTuple _ _ -> pp_as_was
- HsPar _ -> pp_as_was
-
- _ -> parens pp_as_was
+ HsLit l -> ppr l
+ HsOverLit l -> ppr l
+
+ HsVar _ -> pp_as_was
+ HsIPVar _ -> pp_as_was
+ ExplicitList _ _ -> pp_as_was
+ ExplicitPArr _ _ -> pp_as_was
+ ExplicitTuple _ _ -> pp_as_was
+ HsPar _ -> pp_as_was
+
+ _ -> parens pp_as_was
\end{code}
%************************************************************************
data GRHS id
= GRHS [Stmt id] -- The RHS is the final ResultStmt
SrcLoc
-
-mkSimpleMatch :: [Pat id] -> HsExpr id -> Type -> SrcLoc -> Match id
-mkSimpleMatch pats rhs rhs_ty locn
- = Match pats Nothing (GRHSs (unguardedRHS rhs locn) EmptyBinds rhs_ty)
-
-unguardedRHS :: HsExpr id -> SrcLoc -> [GRHS id]
-unguardedRHS rhs loc = [GRHS [ResultStmt rhs loc] loc]
-
-glueBindsOnGRHSs :: HsBinds id -> GRHSs id -> GRHSs id
-glueBindsOnGRHSs EmptyBinds grhss = grhss
-glueBindsOnGRHSs binds1 (GRHSs grhss binds2 ty)
- = GRHSs grhss (binds1 `ThenBinds` binds2) ty
\end{code}
@getMatchLoc@ takes a @Match@ and returns the
%************************************************************************
\begin{code}
-data HsBracket id = ExpBr (HsExpr id)
- | PatBr (Pat id)
- | DecBr (HsGroup id)
- | TypBr (HsType id)
+data HsBracket id = ExpBr (HsExpr id) -- [| expr |]
+ | PatBr (Pat id) -- [p| pat |]
+ | DecBr (HsGroup id) -- [d| decls |]
+ | TypBr (HsType id) -- [t| type |]
+ | VarBr id -- 'x, ''T
instance OutputableBndr id => Outputable (HsBracket id) where
ppr = pprHsBracket
pprHsBracket (PatBr p) = thBrackets (char 'p') (ppr p)
pprHsBracket (DecBr d) = thBrackets (char 'd') (ppr d)
pprHsBracket (TypBr t) = thBrackets (char 't') (ppr t)
-
+pprHsBracket (VarBr n) = char '\'' <> ppr n
+ -- Infelicity: can't show ' vs '', because
+ -- we can't ask n what its OccName is, because the
+ -- pretty-printer for HsExpr doesn't ask for NamedThings
+ -- But the pretty-printer for names will show the OccName class
thBrackets pp_kind pp_body = char '[' <> pp_kind <> char '|' <+>
pp_body <+> ptext SLIT("|]")
-
-data HsReify id = Reify ReifyFlavour id -- Pre typechecking
- | ReifyOut ReifyFlavour Name -- Post typechecking
- -- The Name could be the name of
- -- an Id, TyCon, or Class
-
-data ReifyFlavour = ReifyDecl | ReifyType | ReifyFixity
-
-instance Outputable id => Outputable (HsReify id) where
- ppr (Reify flavour id) = ppr flavour <+> ppr id
- ppr (ReifyOut flavour thing) = ppr flavour <+> ppr thing
-
-instance Outputable ReifyFlavour where
- ppr ReifyDecl = ptext SLIT("reifyDecl")
- ppr ReifyType = ptext SLIT("reifyType")
- ppr ReifyFixity = ptext SLIT("reifyFixity")
\end{code}
%************************************************************************