-- others:
import ForeignCall ( Safety )
import PprType ( pprParendType )
-import Type ( Type, TyThing )
+import Type ( Type )
import Var ( TyVar, Id )
import Name ( Name )
+import NameSet ( FreeVars )
import DataCon ( DataCon )
import CStrings ( CLabelString, pprCLabelString )
import BasicTypes ( IPName, Boxity, tupleParens, Fixity(..) )
| OpApp (HsExpr id) -- left operand
(HsExpr id) -- operator
- Fixity -- Renamer adds fixity; bottom until then
+ Fixity -- Renamer adds fixity; bottom until then
(HsExpr id) -- right operand
-- We preserve prefix negation and parenthesis for the precedence parser.
| HsLet (HsBinds id) -- let(rec)
(HsExpr id)
- | HsWith (HsExpr id) -- implicit parameter binding
- [(IPName id, HsExpr id)]
- Bool -- True <=> this was a 'with' binding
- -- (tmp, until 'with' is removed)
-
| HsDo (HsStmtContext Name) -- The parameterisation is unimportant
-- because in this context we never use
- -- the FunRhs variant
- [Stmt id] -- "do":one or more stmts
- [id] -- Ids for [return,fail,>>=,>>]
- -- Brutal but simple
- -- Before type checking, used for rebindable syntax
- PostTcType -- Type of the whole expression
+ -- the PatGuard or ParStmt variant
+ [Stmt id] -- "do":one or more stmts
+ (ReboundNames id) -- Ids for [return,fail,>>=,>>]
+ PostTcType -- Type of the whole expression
SrcLoc
| ExplicitList -- syntactic list
| HsSCC FastString -- "set cost centre" (_scc_) annotation
(HsExpr id) -- expr whose cost is to be measured
+
+ | HsCoreAnn FastString -- hdaume: core annotation
+ (HsExpr id)
+ -----------------------------------------------------------
-- MetaHaskell Extensions
| HsBracket (HsBracket id) SrcLoc
-- identify this splice point
| HsReify (HsReify id) -- reifyType t, reifyDecl i, reifyFixity
+
+ -----------------------------------------------------------
+ -- Arrow notation extension
+
+ | HsProc (Pat id) -- arrow abstraction, proc
+ (HsCmdTop id) -- body of the abstraction
+ -- always has an empty stack
+ SrcLoc
+
+ ---------------------------------------
+ -- The following are commands, not expressions proper
+
+ | HsArrApp -- Arrow tail, or arrow application (f -< arg)
+ (HsExpr id) -- arrow expression, f
+ (HsExpr id) -- input expression, arg
+ PostTcType -- type of the arrow expressions f,
+ -- of the form a t t', where arg :: t
+ HsArrAppType -- higher-order (-<<) or first-order (-<)
+ Bool -- True => right-to-left (f -< arg)
+ -- False => left-to-right (arg >- f)
+ SrcLoc
+
+ | HsArrForm -- Command formation, (| e |) cmd1 .. cmdn
+ (HsExpr id) -- the operator
+ -- after type-checking, a type abstraction to be
+ -- applied to the type of the local environment tuple
+ (Maybe Fixity) -- fixity (filled in by the renamer), for forms that
+ -- were converted from OpApp's by the renamer
+ [HsCmdTop id] -- argument commands
+ SrcLoc
+
\end{code}
-- pasted back in by the desugarer
\end{code}
+Table of bindings of names used in rebindable syntax.
+This gets filled in by the renamer.
+
+\begin{code}
+type ReboundNames id = [(Name, HsExpr id)]
+-- * Before the renamer, this list is empty
+--
+-- * After the renamer, it takes the form [(std_name, HsVar actual_name)]
+-- For example, for the 'return' op of a monad
+-- normal case: (GHC.Base.return, HsVar GHC.Base.return)
+-- with rebindable syntax: (GHC.Base.return, return_22)
+-- where return_22 is whatever "return" is in scope
+--
+-- * After the type checker, it takes the form [(std_name, <expression>)]
+-- where <expression> is the evidence for the method
+\end{code}
A @Dictionary@, unless of length 0 or 1, becomes a tuple. A
@ClassDictLam dictvars methods expr@ is, therefore:
= hang (pprExpr op) 4 (sep [pp_e1, pp_e2])
pp_infixly v
- = sep [pp_e1, hsep [pp_v_op, pp_e2]]
- where
- ppr_v = ppr v
- pp_v_op | isOperator ppr_v = ppr_v
- | otherwise = char '`' <> ppr_v <> char '`'
- -- Put it in backquotes if it's not an operator already
+ = sep [pp_e1, hsep [pprInfix v, pp_e2]]
ppr_expr (NegApp e _) = char '-' <+> pprParendExpr e
= sep [hang (ptext SLIT("let")) 2 (pprBinds binds),
hang (ptext SLIT("in")) 2 (ppr expr)]
-ppr_expr (HsWith expr binds is_with)
- = sep [hang (ptext SLIT("let")) 2 (pp_ipbinds binds),
- hang (ptext SLIT("in")) 2 (ppr expr)]
-
ppr_expr (HsDo do_or_list_comp stmts _ _ _) = pprDo do_or_list_comp stmts
ppr_expr (ExplicitList _ exprs)
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]
+ppr_expr (HsArrApp arrow arg _ HsFirstOrderApp False _)
+ = hsep [pprExpr arg, ptext SLIT(">-"), pprExpr arrow]
+ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp True _)
+ = hsep [pprExpr arrow, ptext SLIT("-<<"), pprExpr arg]
+ppr_expr (HsArrApp arrow arg _ HsHigherOrderApp False _)
+ = hsep [pprExpr arg, ptext SLIT(">>-"), pprExpr 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 <> ptext SLIT("|)"))
+ 4 (sep (map pprCmdArg args))
+
+pprCmdArg :: OutputableBndr id => HsCmdTop id -> SDoc
+pprCmdArg (HsCmdTop cmd@(HsArrForm _ Nothing [] _) _ _ _) = pprExpr cmd
+pprCmdArg (HsCmdTop cmd _ _ _) = parens (pprExpr cmd)
+
+-- Put a var in backquotes if it's not an operator already
+pprInfix :: Outputable name => name -> SDoc
+pprInfix v | isOperator ppr_v = ppr_v
+ | otherwise = char '`' <> ppr_v <> char '`'
+ where
+ ppr_v = ppr v
+
-- add parallel array brackets around a document
--
pa_brackets :: SDoc -> SDoc
%************************************************************************
%* *
+\subsection{Commands (in arrow abstractions)}
+%* *
+%************************************************************************
+
+We re-use HsExpr to represent these.
+
+\begin{code}
+type HsCmd id = HsExpr id
+
+data HsArrAppType = HsHigherOrderApp | HsFirstOrderApp
+\end{code}
+
+The legal constructors for commands are:
+
+ = HsArrApp ... -- as above
+
+ | HsArrForm ... -- as above
+
+ | HsLam (Match id) -- kappa
+
+ -- the renamer turns this one into HsArrForm
+ | OpApp (HsExpr id) -- left operand
+ (HsCmd id) -- operator
+ Fixity -- Renamer adds fixity; bottom until then
+ (HsCmd id) -- right operand
+
+ | HsPar (HsCmd id) -- parenthesised command
+
+ | HsCase (HsExpr id)
+ [Match id] -- bodies are HsCmd's
+ SrcLoc
+
+ | HsIf (HsExpr id) -- predicate
+ (HsCmd id) -- then part
+ (HsCmd id) -- else part
+ SrcLoc
+
+ | HsLet (HsBinds id) -- let(rec)
+ (HsCmd id)
+
+ | HsDo (HsStmtContext Name) -- The parameterisation is unimportant
+ -- because in this context we never use
+ -- the PatGuard or ParStmt variant
+ [Stmt id] -- HsExpr's are really HsCmd's
+ (ReboundNames id)
+ PostTcType -- Type of the whole expression
+ SrcLoc
+
+Top-level command, introducing a new arrow.
+This may occur inside a proc (where the stack is empty) or as an
+argument of a command-forming operator.
+
+\begin{code}
+data HsCmdTop id
+ = HsCmdTop (HsCmd id)
+ [PostTcType] -- types of inputs on the command's stack
+ PostTcType -- return type of the command
+ (ReboundNames id)
+ -- after type checking:
+ -- names used in the command's desugaring
+\end{code}
+
+%************************************************************************
+%* *
\subsection{Record binds}
%* *
%************************************************************************
pp_rbind (v, e) = hsep [pprBndr LetBind v, char '=', ppr e]
\end{code}
-\begin{code}
-pp_ipbinds :: OutputableBndr id => [(IPName id, HsExpr id)] -> SDoc
-pp_ipbinds pairs = hsep (punctuate semi (map pp_item pairs))
- where
- pp_item (id,rhs) = pprBndr LetBind id <+> equals <+> ppr_expr rhs
-\end{code}
%************************************************************************
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
-- The type is the *element type* of the expression
-- ParStmts only occur in a list comprehension
- | ParStmt [[Stmt id]] -- List comp only: parallel set of quals
- | ParStmtOut [([id], [Stmt id])] -- PLC after renaming; the ids are the binders
- -- bound by the stmts
-
- -- mdo-notation (only exists after renamer)
- -- The ids are a subset of the variables bound by the stmts that
- -- either (a) are used before they are bound in the stmts
- -- or (b) are used in stmts that follow the RecStmt
- | RecStmt [id]
- [Stmt id]
- [HsExpr id] -- Post type-checking only; these expressions correspond
- -- 1-to-1 with the [id], and are the expresions that should
- -- be returned by the recursion. They may not quite be the
- -- Ids themselves, because the Id may be polymorphic, but
- -- the returned thing has to be monomorphic.
+ | ParStmt [([Stmt id], [id])] -- After remaing, the ids are the binders
+ -- bound by the stmts and used subsequently
+
+ -- Recursive statement
+ | RecStmt [Stmt id]
+ --- The next two fields are only valid after renaming
+ [id] -- The ids are a subset of the variables bound by the stmts
+ -- that are used in stmts that follow the RecStmt
+
+ [id] -- Ditto, but these variables are the "recursive" ones, that
+ -- are used before they are bound in the stmts of the RecStmt
+ -- From a type-checking point of view, these ones have to be monomorphic
+
+ --- This field is only valid after typechecking
+ [HsExpr id] -- These expressions correspond
+ -- 1-to-1 with the "recursive" [id], and are the expresions that
+ -- should be returned by the recursion. They may not quite be the
+ -- Ids themselves, because the Id may be *polymorphic*, but
+ -- the returned thing has to be *monomorphic*.
\end{code}
ExprStmts and ResultStmts are a bit tricky, because what they mean
instance OutputableBndr id => Outputable (Stmt id) where
ppr stmt = pprStmt stmt
-pprStmt (BindStmt pat expr _) = hsep [ppr pat, ptext SLIT("<-"), ppr expr]
-pprStmt (LetStmt binds) = hsep [ptext SLIT("let"), pprBinds binds]
-pprStmt (ExprStmt expr _ _) = ppr expr
-pprStmt (ResultStmt expr _) = ppr expr
-pprStmt (ParStmt stmtss)
- = hsep (map (\stmts -> ptext SLIT("| ") <> ppr stmts) stmtss)
-pprStmt (ParStmtOut stmtss)
- = hsep (map (\stmts -> ptext SLIT("| ") <> ppr stmts) stmtss)
-pprStmt (RecStmt _ segment _) = vcat (map ppr segment)
+pprStmt (BindStmt pat expr _) = hsep [ppr pat, ptext SLIT("<-"), ppr expr]
+pprStmt (LetStmt binds) = hsep [ptext SLIT("let"), pprBinds binds]
+pprStmt (ExprStmt expr _ _) = ppr expr
+pprStmt (ResultStmt expr _) = ppr expr
+pprStmt (ParStmt stmtss) = hsep (map (\stmts -> ptext SLIT("| ") <> ppr stmts) stmtss)
+pprStmt (RecStmt segment _ _ _) = ptext SLIT("rec") <+> braces (vcat (map ppr segment))
pprDo :: OutputableBndr id => HsStmtContext any -> [Stmt id] -> SDoc
pprDo DoExpr stmts = hang (ptext SLIT("do")) 2 (vcat (map ppr stmts))
pp_body <+> ptext SLIT("|]")
data HsReify id = Reify ReifyFlavour id -- Pre typechecking
- | ReifyOut ReifyFlavour TyThing -- Post typechecking
+ | ReifyOut ReifyFlavour Name -- Post typechecking
+ -- The Name could be the name of
+ -- an Id, TyCon, or Class
data ReifyFlavour = ReifyDecl | ReifyType | ReifyFixity
= FunRhs id -- Function binding for f
| CaseAlt -- Guard on a case alternative
| LambdaExpr -- Pattern of a lambda
+ | ProcExpr -- Pattern of a proc
| PatBindRhs -- Pattern binding
| RecUpd -- Record update [used only in DsExpr to tell matchWrapper
-- what sort of runtime error message to generate]
| MDoExpr -- Recursive do-expression
| PArrComp -- Parallel array comprehension
| PatGuard (HsMatchContext id) -- Pattern guard for specified thing
+ | ParStmtCtxt (HsStmtContext id) -- A branch of a parallel stmt
\end{code}
\begin{code}
matchSeparator (FunRhs _) = ptext SLIT("=")
matchSeparator CaseAlt = ptext SLIT("->")
matchSeparator LambdaExpr = ptext SLIT("->")
+matchSeparator ProcExpr = ptext SLIT("->")
matchSeparator PatBindRhs = ptext SLIT("=")
matchSeparator (StmtCtxt _) = ptext SLIT("<-")
matchSeparator RecUpd = panic "unused"
pprMatchContext RecUpd = ptext SLIT("a record-update construct")
pprMatchContext PatBindRhs = ptext SLIT("a pattern binding")
pprMatchContext LambdaExpr = ptext SLIT("a lambda abstraction")
+pprMatchContext ProcExpr = ptext SLIT("an arrow abstraction")
pprMatchContext (StmtCtxt ctxt) = ptext SLIT("a pattern binding in") $$ pprStmtContext ctxt
pprMatchRhsContext (FunRhs fun) = ptext SLIT("a right-hand side of function") <+> quotes (ppr fun)
pprMatchRhsContext CaseAlt = ptext SLIT("the body of a case alternative")
pprMatchRhsContext PatBindRhs = ptext SLIT("the right-hand side of a pattern binding")
pprMatchRhsContext LambdaExpr = ptext SLIT("the body of a lambda")
+pprMatchRhsContext ProcExpr = ptext SLIT("the body of a proc")
pprMatchRhsContext RecUpd = panic "pprMatchRhsContext"
+pprStmtContext (ParStmtCtxt c) = sep [ptext SLIT("a parallel branch of"), pprStmtContext c]
pprStmtContext (PatGuard ctxt) = ptext SLIT("a pattern guard for") $$ pprMatchContext ctxt
pprStmtContext DoExpr = ptext SLIT("a 'do' expression")
pprStmtContext MDoExpr = ptext SLIT("an 'mdo' expression")
-- Used to generate the string for a *runtime* error message
-matchContextErrString (FunRhs fun) = "function " ++ showSDoc (ppr fun)
-matchContextErrString CaseAlt = "case"
-matchContextErrString PatBindRhs = "pattern binding"
-matchContextErrString RecUpd = "record update"
-matchContextErrString LambdaExpr = "lambda"
-matchContextErrString (StmtCtxt (PatGuard _)) = "pattern gaurd"
-matchContextErrString (StmtCtxt DoExpr) = "'do' expression"
-matchContextErrString (StmtCtxt MDoExpr) = "'mdo' expression"
-matchContextErrString (StmtCtxt ListComp) = "list comprehension"
-matchContextErrString (StmtCtxt PArrComp) = "array comprehension"
+matchContextErrString (FunRhs fun) = "function " ++ showSDoc (ppr fun)
+matchContextErrString CaseAlt = "case"
+matchContextErrString PatBindRhs = "pattern binding"
+matchContextErrString RecUpd = "record update"
+matchContextErrString LambdaExpr = "lambda"
+matchContextErrString ProcExpr = "proc"
+matchContextErrString (StmtCtxt (ParStmtCtxt c)) = matchContextErrString (StmtCtxt c)
+matchContextErrString (StmtCtxt (PatGuard _)) = "pattern guard"
+matchContextErrString (StmtCtxt DoExpr) = "'do' expression"
+matchContextErrString (StmtCtxt MDoExpr) = "'mdo' expression"
+matchContextErrString (StmtCtxt ListComp) = "list comprehension"
+matchContextErrString (StmtCtxt PArrComp) = "array comprehension"
\end{code}
projects / ghc-hetmet.git / blobdiff