-- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings
-- for details
-module RnBinds (
- rnTopBinds,
- rnLocalBindsAndThen, rnValBindsAndThen, rnValBinds, trimWith,
- rnMethodBinds, renameSigs, mkSigTvFn,
- rnMatchGroup, rnGRHSs
+module RnBinds (rnTopBinds, rnTopBindsLHS, rnTopBindsRHS, -- use these for top-level bindings
+ rnLocalBindsAndThen, rnValBindsLHS, rnValBindsRHS, -- or these for local bindings
+ rnMethodBinds, renameSigs, mkSigTvFn,
+ rnMatchGroup, rnGRHSs,
+ makeMiniFixityEnv, MiniFixityEnv
) where
#include "HsVersions.h"
import RdrHsSyn
import RnHsSyn
import TcRnMonad
-import RnTypes ( rnHsSigType, rnLHsType, rnHsTypeFVs,
- rnLPat, rnPatsAndThen, patSigErr, checkPrecMatch )
-import RnEnv ( bindLocatedLocalsRn, lookupLocatedBndrRn,
- lookupInstDeclBndr, newIPNameRn,
- lookupLocatedSigOccRn, bindPatSigTyVarsFV,
- bindLocalFixities, bindSigTyVarsFV,
- warnUnusedLocalBinds, mapFvRn, extendTyVarEnvFVRn,
- )
+import RnTypes ( rnHsSigType, rnLHsType, rnHsTypeFVs,checkPrecMatch)
+import RnPat (rnPatsAndThen_LocalRightwards, rnBindPat,
+ NameMaker, localRecNameMaker, topRecNameMaker, applyNameMaker,
+ patSigErr)
+
+import RnEnv
import DynFlags ( DynFlag(..) )
+import HscTypes (FixItem(..))
import Name
import NameEnv
+import LazyUniqFM
import NameSet
import PrelNames ( isUnboundName )
import RdrName ( RdrName, rdrNameOcc )
-import SrcLoc ( Located(..), unLoc )
+import SrcLoc ( Located(..), unLoc, noLoc )
import ListSetOps ( findDupsEq )
import BasicTypes ( RecFlag(..) )
import Digraph ( SCC(..), stronglyConnComp )
import Bag
import Outputable
+import FastString
import Maybes ( orElse )
import Util ( filterOut )
-import Monad ( foldM )
+import Monad ( foldM, unless )
\end{code}
-- ToDo: Put the annotations into the monad, so that they arrive in the proper
%* *
%************************************************************************
-@rnTopMonoBinds@ assumes that the environment already
-contains bindings for the binders of this particular binding.
-
\begin{code}
-rnTopBinds :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses)
-
--- The binders of the binding are in scope already;
--- the top level scope resolution does that
-
-rnTopBinds binds
- = do { is_boot <- tcIsHsBoot
- ; if is_boot then rnTopBindsBoot binds
- else rnTopBindsSrc binds }
-
-rnTopBindsBoot :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses)
+-- for top-level bindings, we need to make top-level names,
+-- so we have a different entry point than for local bindings
+rnTopBindsLHS :: MiniFixityEnv
+ -> HsValBinds RdrName
+ -> RnM (HsValBindsLR Name RdrName)
+rnTopBindsLHS fix_env binds =
+ (uncurry $ rnValBindsLHSFromDoc (topRecNameMaker fix_env)) (bindersAndDoc binds) binds
+
+rnTopBindsRHS :: [Name] -- the names bound by these binds
+ -> HsValBindsLR Name RdrName
+ -> RnM (HsValBinds Name, DefUses)
+rnTopBindsRHS bound_names binds =
+ do { is_boot <- tcIsHsBoot
+ ; if is_boot
+ then rnTopBindsBoot binds
+ else rnValBindsRHSGen (\x -> x) -- don't trim free vars
+ bound_names binds }
+
+
+-- wrapper if we don't need to do anything in between the left and right,
+-- or anything else in the scope of the left
+--
+-- never used when there are fixity declarations
+rnTopBinds :: HsValBinds RdrName
+ -> RnM (HsValBinds Name, DefUses)
+rnTopBinds b =
+ do nl <- rnTopBindsLHS emptyOccEnv b
+ let bound_names = map unLoc (collectHsValBinders nl)
+ bindLocalNames bound_names $ rnTopBindsRHS bound_names nl
+
+
+rnTopBindsBoot :: HsValBindsLR Name RdrName -> RnM (HsValBinds Name, DefUses)
-- A hs-boot file has no bindings.
-- Return a single HsBindGroup with empty binds and renamed signatures
rnTopBindsBoot (ValBindsIn mbinds sigs)
= do { checkErr (isEmptyLHsBinds mbinds) (bindsInHsBootFile mbinds)
; sigs' <- renameSigs okHsBootSig sigs
; return (ValBindsOut [] sigs', usesOnly (hsSigsFVs sigs')) }
-
-rnTopBindsSrc :: HsValBinds RdrName -> RnM (HsValBinds Name, DefUses)
-rnTopBindsSrc binds = rnValBinds noTrim binds
\end{code}
%*********************************************************
\begin{code}
-rnLocalBindsAndThen
- :: HsLocalBinds RdrName
- -> (HsLocalBinds Name -> RnM (result, FreeVars))
- -> RnM (result, FreeVars)
--- This version (a) assumes that the binding vars are not already in scope
--- (b) removes the binders from the free vars of the thing inside
+rnLocalBindsAndThen :: HsLocalBinds RdrName
+ -> (HsLocalBinds Name -> RnM (result, FreeVars))
+ -> RnM (result, FreeVars)
+-- This version (a) assumes that the binding vars are *not* already in scope
+-- (b) removes the binders from the free vars of the thing inside
-- The parser doesn't produce ThenBinds
rnLocalBindsAndThen EmptyLocalBinds thing_inside
= thing_inside EmptyLocalBinds
rnLocalBindsAndThen (HsValBinds val_binds) thing_inside
= rnValBindsAndThen val_binds $ \ val_binds' ->
- thing_inside (HsValBinds val_binds')
+ thing_inside (HsValBinds val_binds')
-rnLocalBindsAndThen (HsIPBinds binds) thing_inside
- = rnIPBinds binds `thenM` \ (binds',fv_binds) ->
- thing_inside (HsIPBinds binds') `thenM` \ (thing, fvs_thing) ->
- returnM (thing, fvs_thing `plusFV` fv_binds)
+rnLocalBindsAndThen (HsIPBinds binds) thing_inside = do
+ (binds',fv_binds) <- rnIPBinds binds
+ (thing, fvs_thing) <- thing_inside (HsIPBinds binds')
+ return (thing, fvs_thing `plusFV` fv_binds)
--------------
-rnIPBinds (IPBinds ip_binds _no_dict_binds)
- = do { (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds
- ; return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s) }
-rnIPBind (IPBind n expr)
- = newIPNameRn n `thenM` \ name ->
- rnLExpr expr `thenM` \ (expr',fvExpr) ->
+rnIPBinds (IPBinds ip_binds _no_dict_binds) = do
+ (ip_binds', fvs_s) <- mapAndUnzipM (wrapLocFstM rnIPBind) ip_binds
+ return (IPBinds ip_binds' emptyLHsBinds, plusFVs fvs_s)
+
+rnIPBind (IPBind n expr) = do
+ name <- newIPNameRn n
+ (expr',fvExpr) <- rnLExpr expr
return (IPBind name expr', fvExpr)
\end{code}
%************************************************************************
\begin{code}
-rnValBindsAndThen :: HsValBinds RdrName
- -> (HsValBinds Name -> RnM (result, FreeVars))
- -> RnM (result, FreeVars)
-
-rnValBindsAndThen binds@(ValBindsIn mbinds sigs) thing_inside
- = -- Extract all the binders in this group, and extend the
- -- current scope, inventing new names for the new binders
- -- This also checks that the names form a set
- bindLocatedLocalsRn doc mbinders_w_srclocs $ \ bndrs ->
-
- -- Then install local fixity declarations
- -- Notice that they scope over thing_inside too
- bindLocalFixities [sig | L _ (FixSig sig) <- sigs ] $
-
- -- Do the business
- rnValBinds (trimWith bndrs) binds `thenM` \ (binds, bind_dus) ->
-
- -- Now do the "thing inside"
- thing_inside binds `thenM` \ (result,result_fvs) ->
-
- -- Final error checking
+-- wrapper for local binds
+-- creates the documentation info and calls the helper below
+rnValBindsLHS :: MiniFixityEnv
+ -> HsValBinds RdrName
+ -> RnM (HsValBindsLR Name RdrName)
+rnValBindsLHS fix_env binds =
+ let (boundNames,doc) = bindersAndDoc binds
+ in rnValBindsLHSFromDoc_Local boundNames doc fix_env binds
+
+-- a helper used for local binds that does the duplicates check,
+-- just so we don't forget to do it somewhere
+rnValBindsLHSFromDoc_Local :: [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice)
+ -> SDoc -- doc string for dup names and shadowing
+ -> MiniFixityEnv
+ -> HsValBinds RdrName
+ -> RnM (HsValBindsLR Name RdrName)
+
+rnValBindsLHSFromDoc_Local boundNames doc fix_env binds = do
+ -- Do error checking: we need to check for dups here because we
+ -- don't don't bind all of the variables from the ValBinds at once
+ -- with bindLocatedLocals any more.
+ checkDupAndShadowedRdrNames doc boundNames
+
+ -- (Note that we don't want to do this at the top level, since
+ -- sorting out duplicates and shadowing there happens elsewhere.
+ -- The behavior is even different. For example,
+ -- import A(f)
+ -- f = ...
+ -- should not produce a shadowing warning (but it will produce
+ -- an ambiguity warning if you use f), but
+ -- import A(f)
+ -- g = let f = ... in f
+ -- should.
+ rnValBindsLHSFromDoc (localRecNameMaker fix_env) boundNames doc binds
+
+bindersAndDoc :: HsValBinds RdrName -> ([Located RdrName], SDoc)
+bindersAndDoc binds =
let
- all_uses = duUses bind_dus `plusFV` result_fvs
- -- duUses: It's important to return all the uses, not the 'real uses'
- -- used for warning about unused bindings. Otherwise consider:
- -- x = 3
- -- y = let p = x in 'x' -- NB: p not used
- -- If we don't "see" the dependency of 'y' on 'x', we may put the
- -- bindings in the wrong order, and the type checker will complain
- -- that x isn't in scope
-
- unused_bndrs = [ b | b <- bndrs, not (b `elemNameSet` all_uses)]
+ -- the unrenamed bndrs for error checking and reporting
+ orig = collectHsValBinders binds
+ doc = text "In the binding group for:" <+> pprWithCommas ppr (map unLoc orig)
in
- warnUnusedLocalBinds unused_bndrs `thenM_`
+ (orig, doc)
+
+-- renames the left-hand sides
+-- generic version used both at the top level and for local binds
+-- does some error checking, but not what gets done elsewhere at the top level
+rnValBindsLHSFromDoc :: NameMaker
+ -> [Located RdrName] -- RdrNames of the LHS (so we don't have to gather them twice)
+ -> SDoc -- doc string for dup names and shadowing
+ -> HsValBinds RdrName
+ -> RnM (HsValBindsLR Name RdrName)
+rnValBindsLHSFromDoc topP original_bndrs doc binds@(ValBindsIn mbinds sigs) = do
+ -- rename the LHSes
+ mbinds' <- mapBagM (rnBindLHS topP doc) mbinds
+ return $ ValBindsIn mbinds' sigs
+
+-- assumes the LHS vars are in scope
+-- general version used both from the top-level and for local things
+--
+-- does not bind the local fixity declarations
+rnValBindsRHSGen :: (FreeVars -> FreeVars) -- for trimming free var sets
+ -- The trimming function trims the free vars we attach to a
+ -- binding so that it stays reasonably small
+ -> [Name] -- names bound by the LHSes
+ -> HsValBindsLR Name RdrName
+ -> RnM (HsValBinds Name, DefUses)
+
+rnValBindsRHSGen trim bound_names binds@(ValBindsIn mbinds sigs) = do
+ -- rename the sigs
+ env <- getGblEnv
+ traceRn (ptext SLIT("Rename sigs") <+> ppr (tcg_rdr_env env))
+ sigs' <- rename_sigs sigs
+ -- rename the RHSes
+ binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds
+ let (anal_binds, anal_dus) = depAnalBinds binds_w_dus
+ (valbind', valbind'_dus) = (ValBindsOut anal_binds sigs',
+ usesOnly (hsSigsFVs sigs') `plusDU` anal_dus)
+ -- We do the check-sigs after renaming the bindings,
+ -- so that we have convenient access to the binders
+ check_sigs (okBindSig (duDefs anal_dus)) sigs'
+ return (valbind', valbind'_dus)
+
+-- Wrapper for local binds
+--
+-- The *client* of this function is responsible for checking for unused binders;
+-- it doesn't (and can't: we don't have the thing inside the binds) happen here
+--
+-- The client is also responsible for bringing the fixities into scope
+rnValBindsRHS :: [Name] -- names bound by the LHSes
+ -> HsValBindsLR Name RdrName
+ -> RnM (HsValBinds Name, DefUses)
+rnValBindsRHS bound_names binds =
+ rnValBindsRHSGen (\ fvs -> -- only keep the names the names from this group
+ intersectNameSet (mkNameSet bound_names) fvs) bound_names binds
- returnM (result, delListFromNameSet all_uses bndrs)
- where
- mbinders_w_srclocs = collectHsBindLocatedBinders mbinds
- doc = text "In the binding group for:"
- <+> pprWithCommas ppr (map unLoc mbinders_w_srclocs)
+
+-- for local binds
+-- wrapper that does both the left- and right-hand sides
+--
+-- here there are no local fixity decls passed in;
+-- the local fixity decls come from the ValBinds sigs
+rnValBindsAndThen :: HsValBinds RdrName
+ -> (HsValBinds Name -> RnM (result, FreeVars))
+ -> RnM (result, FreeVars)
+rnValBindsAndThen binds@(ValBindsIn _ sigs) thing_inside
+ = do { let (original_bndrs, doc) = bindersAndDoc binds
+
+ -- (A) Create the local fixity environment
+ ; new_fixities <- makeMiniFixityEnv [L loc sig | L loc (FixSig sig) <- sigs]
+
+ -- (B) Rename the LHSes
+ ; new_lhs <- rnValBindsLHSFromDoc_Local original_bndrs doc new_fixities binds
+ ; let bound_names = map unLoc $ collectHsValBinders new_lhs
+
+ -- ...and bring them (and their fixities) into scope
+ ; bindLocalNamesFV_WithFixities bound_names new_fixities $ do
+
+ { -- (C) Do the RHS and thing inside
+ (binds', dus) <- rnValBindsRHS bound_names new_lhs
+ ; (result, result_fvs) <- thing_inside binds'
+
+ -- Report unused bindings based on the (accurate)
+ -- findUses. E.g.
+ -- let x = x in 3
+ -- should report 'x' unused
+ ; let real_uses = findUses dus result_fvs
+ ; warnUnusedLocalBinds bound_names real_uses
+
+ ; let
+ -- The variables "used" in the val binds are:
+ -- (1) the uses of the binds (duUses)
+ -- (2) the FVs of the thing-inside
+ all_uses = duUses dus `plusFV` result_fvs
+ -- Note [Unused binding hack]
+ -- ~~~~~~~~~~~~~~~~~~~~~~~~~~
+ -- Note that *in contrast* to the above reporting of
+ -- unused bindings, (1) above uses duUses to return *all*
+ -- the uses, even if the binding is unused. Otherwise consider:
+ -- x = 3
+ -- y = let p = x in 'x' -- NB: p not used
+ -- If we don't "see" the dependency of 'y' on 'x', we may put the
+ -- bindings in the wrong order, and the type checker will complain
+ -- that x isn't in scope
+ --
+ -- But note that this means we won't report 'x' as unused,
+ -- whereas we would if we had { x = 3; p = x; y = 'x' }
+
+ ; return (result, all_uses) }}
+ -- The bound names are pruned out of all_uses
+ -- by the bindLocalNamesFV call above
+
+
+
+-- Process the fixity declarations, making a FastString -> (Located Fixity) map
+-- (We keep the location around for reporting duplicate fixity declarations.)
+--
+-- Checks for duplicates, but not that only locally defined things are fixed.
+-- Note: for local fixity declarations, duplicates would also be checked in
+-- check_sigs below. But we also use this function at the top level.
+
+makeMiniFixityEnv :: [LFixitySig RdrName] -> RnM MiniFixityEnv
+
+makeMiniFixityEnv decls = foldlM add_one emptyOccEnv decls
+ where
+ add_one env (L loc (FixitySig (L name_loc name) fixity)) = do
+ { -- this fixity decl is a duplicate iff
+ -- the ReaderName's OccName's FastString is already in the env
+ -- (we only need to check the local fix_env because
+ -- definitions of non-local will be caught elsewhere)
+ let {occ = rdrNameOcc name;
+ fix_item = L loc fixity};
+
+ case lookupOccEnv env occ of
+ Nothing -> return $ extendOccEnv env occ fix_item
+ Just (L loc' _) -> do
+ { setSrcSpan loc $
+ addLocErr (L name_loc name) (dupFixityDecl loc')
+ ; return env}
+ }
+
+pprFixEnv :: NameEnv FixItem -> SDoc
+pprFixEnv env
+ = pprWithCommas (\ (FixItem n f) -> ppr f <+> ppr n)
+ (nameEnvElts env)
+
+dupFixityDecl loc rdr_name
+ = vcat [ptext SLIT("Multiple fixity declarations for") <+> quotes (ppr rdr_name),
+ ptext SLIT("also at ") <+> ppr loc]
---------------------
-rnValBinds :: (FreeVars -> FreeVars)
- -> HsValBinds RdrName
- -> RnM (HsValBinds Name, DefUses)
--- Assumes the binders of the binding are in scope already
-rnValBinds trim (ValBindsIn mbinds sigs)
- = do { sigs' <- rename_sigs sigs
+-- renaming a single bind
+
+rnBindLHS :: NameMaker
+ -> SDoc
+ -> LHsBind RdrName
+ -- returns the renamed left-hand side,
+ -- and the FreeVars *of the LHS*
+ -- (i.e., any free variables of the pattern)
+ -> RnM (LHsBindLR Name RdrName)
+
+rnBindLHS name_maker doc (L loc (PatBind { pat_lhs = pat,
+ pat_rhs = grhss,
+ bind_fvs=bind_fvs,
+ pat_rhs_ty=pat_rhs_ty
+ }))
+ = setSrcSpan loc $ do
+ -- we don't actually use the FV processing of rnPatsAndThen here
+ (pat',pat'_fvs) <- rnBindPat name_maker pat
+ return (L loc (PatBind { pat_lhs = pat',
+ pat_rhs = grhss,
+ -- we temporarily store the pat's FVs here;
+ -- gets updated to the FVs of the whole bind
+ -- when doing the RHS below
+ bind_fvs = pat'_fvs,
+ -- these will get ignored in the next pass,
+ -- when we rename the RHS
+ pat_rhs_ty = pat_rhs_ty }))
+
+rnBindLHS name_maker doc (L loc (FunBind { fun_id = name@(L nameLoc _),
+ fun_infix = inf,
+ fun_matches = matches,
+ fun_co_fn = fun_co_fn,
+ bind_fvs = bind_fvs,
+ fun_tick = fun_tick
+ }))
+ = setSrcSpan loc $
+ do { (newname, _fvs) <- applyNameMaker name_maker name $ \ newname ->
+ return (newname, emptyFVs)
+ ; return (L loc (FunBind { fun_id = L nameLoc newname,
+ fun_infix = inf,
+ fun_matches = matches,
+ -- we temporatily store the LHS's FVs (empty in this case) here
+ -- gets updated when doing the RHS below
+ bind_fvs = emptyFVs,
+ -- everything else will get ignored in the next pass
+ fun_co_fn = fun_co_fn,
+ fun_tick = fun_tick
+ })) }
+
+-- assumes the left-hands-side vars are in scope
+rnBind :: (Name -> [Name]) -- Signature tyvar function
+ -> (FreeVars -> FreeVars) -- Trimming function for rhs free vars
+ -> LHsBindLR Name RdrName
+ -> RnM (LHsBind Name, [Name], Uses)
+rnBind sig_fn trim (L loc (PatBind { pat_lhs = pat,
+ pat_rhs = grhss,
+ -- pat fvs were stored here while processing the LHS
+ bind_fvs=pat_fvs }))
+ = setSrcSpan loc $
+ do {let bndrs = collectPatBinders pat
- ; binds_w_dus <- mapBagM (rnBind (mkSigTvFn sigs') trim) mbinds
+ ; (grhss', fvs) <- rnGRHSs PatBindRhs grhss
+ -- No scoped type variables for pattern bindings
- ; let (binds', bind_dus) = depAnalBinds binds_w_dus
+ ; return (L loc (PatBind { pat_lhs = pat,
+ pat_rhs = grhss',
+ pat_rhs_ty = placeHolderType,
+ bind_fvs = trim fvs }),
+ bndrs, pat_fvs `plusFV` fvs) }
- -- We do the check-sigs after renaming the bindings,
- -- so that we have convenient access to the binders
- ; check_sigs (okBindSig (duDefs bind_dus)) sigs'
+rnBind sig_fn
+ trim
+ (L loc (FunBind { fun_id = name,
+ fun_infix = inf,
+ fun_matches = matches,
+ -- no pattern FVs
+ bind_fvs = _
+ }))
+ -- invariant: no free vars here when it's a FunBind
+ = setSrcSpan loc $
+ do { let plain_name = unLoc name
- ; return (ValBindsOut binds' sigs',
- usesOnly (hsSigsFVs sigs') `plusDU` bind_dus) }
+ ; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $
+ -- bindSigTyVars tests for Opt_ScopedTyVars
+ rnMatchGroup (FunRhs plain_name inf) matches
+ ; checkPrecMatch inf plain_name matches'
+ ; return (L loc (FunBind { fun_id = name,
+ fun_infix = inf,
+ fun_matches = matches',
+ bind_fvs = trim fvs,
+ fun_co_fn = idHsWrapper,
+ fun_tick = Nothing }),
+ [plain_name], fvs)
+ }
+
---------------------
depAnalBinds :: Bag (LHsBind Name, [Name], Uses)
-> ([(RecFlag, LHsBinds Name)], DefUses)
(L _ (HsForAllTy Explicit ltvs _ _))) <- sigs]
-- Note the pattern-match on "Explicit"; we only bind
-- type variables from signatures with an explicit top-level for-all
-
--- The trimming function trims the free vars we attach to a
--- binding so that it stays reasonably small
-noTrim :: FreeVars -> FreeVars
-noTrim fvs = fvs -- Used at top level
-
-trimWith :: [Name] -> FreeVars -> FreeVars
--- Nested bindings; trim by intersection with the names bound here
-trimWith bndrs = intersectNameSet (mkNameSet bndrs)
-
----------------------
-rnBind :: (Name -> [Name]) -- Signature tyvar function
- -> (FreeVars -> FreeVars) -- Trimming function for rhs free vars
- -> LHsBind RdrName
- -> RnM (LHsBind Name, [Name], Uses)
-rnBind sig_fn trim (L loc (PatBind { pat_lhs = pat, pat_rhs = grhss }))
- = setSrcSpan loc $
- do { (pat', pat_fvs) <- rnLPat pat
-
- ; let bndrs = collectPatBinders pat'
-
- ; (grhss', fvs) <- rnGRHSs PatBindRhs grhss
- -- No scoped type variables for pattern bindings
-
- ; return (L loc (PatBind { pat_lhs = pat', pat_rhs = grhss',
- pat_rhs_ty = placeHolderType, bind_fvs = trim fvs }),
- bndrs, pat_fvs `plusFV` fvs) }
-
-rnBind sig_fn trim (L loc (FunBind { fun_id = name, fun_infix = inf, fun_matches = matches }))
- = setSrcSpan loc $
- do { new_name <- lookupLocatedBndrRn name
- ; let plain_name = unLoc new_name
-
- ; (matches', fvs) <- bindSigTyVarsFV (sig_fn plain_name) $
- -- bindSigTyVars tests for Opt_ScopedTyVars
- rnMatchGroup (FunRhs plain_name inf) matches
-
- ; checkPrecMatch inf plain_name matches'
-
- ; return (L loc (FunBind { fun_id = new_name, fun_infix = inf, fun_matches = matches',
- bind_fvs = trim fvs, fun_co_fn = idHsWrapper, fun_tick = Nothing }),
- [plain_name], fvs)
- }
\end{code}
rnMethodBind cls sig_fn gen_tyvars (L loc (FunBind { fun_id = name, fun_infix = inf,
fun_matches = MatchGroup matches _ }))
- = setSrcSpan loc $
- lookupInstDeclBndr cls name `thenM` \ sel_name ->
- let plain_name = unLoc sel_name in
- -- We use the selector name as the binder
-
- bindSigTyVarsFV (sig_fn plain_name) $
- mapFvRn (rn_match plain_name) matches `thenM` \ (new_matches, fvs) ->
- let
- new_group = MatchGroup new_matches placeHolderType
- in
- checkPrecMatch inf plain_name new_group `thenM_`
- returnM (unitBag (L loc (FunBind {
- fun_id = sel_name, fun_infix = inf,
- fun_matches = new_group,
- bind_fvs = fvs, fun_co_fn = idHsWrapper,
- fun_tick = Nothing })),
- fvs `addOneFV` plain_name)
- -- The 'fvs' field isn't used for method binds
+ = setSrcSpan loc $ do
+ sel_name <- lookupInstDeclBndr cls name
+ let plain_name = unLoc sel_name
+ -- We use the selector name as the binder
+
+ bindSigTyVarsFV (sig_fn plain_name) $ do
+ (new_matches, fvs) <- mapFvRn (rn_match plain_name) matches
+ let
+ new_group = MatchGroup new_matches placeHolderType
+
+ checkPrecMatch inf plain_name new_group
+ return (unitBag (L loc (FunBind {
+ fun_id = sel_name, fun_infix = inf,
+ fun_matches = new_group,
+ bind_fvs = fvs, fun_co_fn = idHsWrapper,
+ fun_tick = Nothing })),
+ fvs `addOneFV` plain_name)
+ -- The 'fvs' field isn't used for method binds
where
-- Truly gruesome; bring into scope the correct members of the generic
-- type variables. See comments in RnSource.rnSourceDecl(ClassDecl)
-- Can't handle method pattern-bindings which bind multiple methods.
-rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _))
- = addLocErr mbind methodBindErr `thenM_`
- returnM (emptyBag, emptyFVs)
+rnMethodBind cls sig_fn gen_tyvars mbind@(L loc (PatBind other_pat _ _ _)) = do
+ addLocErr mbind methodBindErr
+ return (emptyBag, emptyFVs)
\end{code}
\begin{code}
renameSigs :: (LSig Name -> Bool) -> [LSig RdrName] -> RnM [LSig Name]
-- Renames the signatures and performs error checks
-renameSigs ok_sig sigs
+renameSigs ok_sig sigs
= do { sigs' <- rename_sigs sigs
; check_sigs ok_sig sigs'
; return sigs' }
----------------------
rename_sigs :: [LSig RdrName] -> RnM [LSig Name]
-rename_sigs sigs = mappM (wrapLocM renameSig)
- (filter (not . isFixityLSig) sigs)
- -- Remove fixity sigs which have been dealt with already
+rename_sigs sigs = mapM (wrapLocM renameSig) sigs
----------------------
check_sigs :: (LSig Name -> Bool) -> [LSig Name] -> RnM ()
-- Used for class and instance decls, as well as regular bindings
-check_sigs ok_sig sigs
+check_sigs ok_sig sigs = do
-- Check for (a) duplicate signatures
- -- (b) signatures for things not in this group
- = do { mappM_ unknownSigErr (filter (not . ok_sig) sigs')
- ; mappM_ dupSigDeclErr (findDupsEq eqHsSig sigs') }
+ -- (b) signatures for things not in this group = do
+ traceRn (text "SIGS" <+> ppr sigs)
+ mapM_ unknownSigErr (filter (not . ok_sig) sigs')
+ mapM_ dupSigDeclErr (findDupsEq eqHsSig sigs')
where
-- Don't complain about an unbound name again
sigs' = filterOut bad_name sigs
renameSig :: Sig RdrName -> RnM (Sig Name)
-- FixitSig is renamed elsewhere.
-renameSig (TypeSig v ty)
- = lookupLocatedSigOccRn v `thenM` \ new_v ->
- rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty ->
- returnM (TypeSig new_v new_ty)
-
-renameSig (SpecInstSig ty)
- = rnLHsType (text "A SPECIALISE instance pragma") ty `thenM` \ new_ty ->
- returnM (SpecInstSig new_ty)
-
-renameSig (SpecSig v ty inl)
- = lookupLocatedSigOccRn v `thenM` \ new_v ->
- rnHsSigType (quotes (ppr v)) ty `thenM` \ new_ty ->
- returnM (SpecSig new_v new_ty inl)
-
-renameSig (InlineSig v s)
- = lookupLocatedSigOccRn v `thenM` \ new_v ->
- returnM (InlineSig new_v s)
+renameSig (TypeSig v ty) = do
+ new_v <- lookupLocatedSigOccRn v
+ new_ty <- rnHsSigType (quotes (ppr v)) ty
+ return (TypeSig new_v new_ty)
+
+renameSig (SpecInstSig ty) = do
+ new_ty <- rnLHsType (text "A SPECIALISE instance pragma") ty
+ return (SpecInstSig new_ty)
+
+renameSig (SpecSig v ty inl) = do
+ new_v <- lookupLocatedSigOccRn v
+ new_ty <- rnHsSigType (quotes (ppr v)) ty
+ return (SpecSig new_v new_ty inl)
+
+renameSig (InlineSig v s) = do
+ new_v <- lookupLocatedSigOccRn v
+ return (InlineSig new_v s)
+
+renameSig (FixSig (FixitySig v f)) = do
+ new_v <- lookupLocatedSigOccRn v
+ return (FixSig (FixitySig new_v f))
\end{code}
\begin{code}
rnMatchGroup :: HsMatchContext Name -> MatchGroup RdrName -> RnM (MatchGroup Name, FreeVars)
-rnMatchGroup ctxt (MatchGroup ms _)
- = mapFvRn (rnMatch ctxt) ms `thenM` \ (new_ms, ms_fvs) ->
- returnM (MatchGroup new_ms placeHolderType, ms_fvs)
+rnMatchGroup ctxt (MatchGroup ms _) = do
+ (new_ms, ms_fvs) <- mapFvRn (rnMatch ctxt) ms
+ return (MatchGroup new_ms placeHolderType, ms_fvs)
rnMatch :: HsMatchContext Name -> LMatch RdrName -> RnM (LMatch Name, FreeVars)
rnMatch ctxt = wrapLocFstM (rnMatch' ctxt)
rnMatch' ctxt match@(Match pats maybe_rhs_sig grhss)
=
-- Deal with the rhs type signature
- bindPatSigTyVarsFV rhs_sig_tys $
- doptM Opt_PatternSignatures `thenM` \ opt_PatternSignatures ->
- (case maybe_rhs_sig of
- Nothing -> returnM (Nothing, emptyFVs)
- Just ty | opt_PatternSignatures -> rnHsTypeFVs doc_sig ty `thenM` \ (ty', ty_fvs) ->
- returnM (Just ty', ty_fvs)
- | otherwise -> addLocErr ty patSigErr `thenM_`
- returnM (Nothing, emptyFVs)
- ) `thenM` \ (maybe_rhs_sig', ty_fvs) ->
-
- -- Now the main event
- rnPatsAndThen ctxt pats $ \ pats' ->
- rnGRHSs ctxt grhss `thenM` \ (grhss', grhss_fvs) ->
-
- returnM (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs)
+ bindPatSigTyVarsFV rhs_sig_tys $ do
+ opt_PatternSignatures <- doptM Opt_PatternSignatures
+ (maybe_rhs_sig', ty_fvs) <-
+ case maybe_rhs_sig of
+ Nothing -> return (Nothing, emptyFVs)
+ Just ty | opt_PatternSignatures -> do (ty', ty_fvs) <- rnHsTypeFVs doc_sig ty
+ return (Just ty', ty_fvs)
+ | otherwise -> do addLocErr ty patSigErr
+ return (Nothing, emptyFVs)
+
+ -- Now the main event
+ -- note that there are no local ficity decls for matches
+ rnPatsAndThen_LocalRightwards ctxt pats $ \ pats' -> do
+ (grhss', grhss_fvs) <- rnGRHSs ctxt grhss
+
+ return (Match pats' maybe_rhs_sig' grhss', grhss_fvs `plusFV` ty_fvs)
-- The bindPatSigTyVarsFV and rnPatsAndThen will remove the bound FVs
where
rhs_sig_tys = case maybe_rhs_sig of
rnGRHSs :: HsMatchContext Name -> GRHSs RdrName -> RnM (GRHSs Name, FreeVars)
rnGRHSs ctxt (GRHSs grhss binds)
- = rnLocalBindsAndThen binds $ \ binds' ->
- mapFvRn (rnGRHS ctxt) grhss `thenM` \ (grhss', fvGRHSs) ->
- returnM (GRHSs grhss' binds', fvGRHSs)
+ = rnLocalBindsAndThen binds $ \ binds' -> do
+ (grhss', fvGRHSs) <- mapFvRn (rnGRHS ctxt) grhss
+ return (GRHSs grhss' binds', fvGRHSs)
rnGRHS :: HsMatchContext Name -> LGRHS RdrName -> RnM (LGRHS Name, FreeVars)
rnGRHS ctxt = wrapLocFstM (rnGRHS' ctxt)
; ((guards', rhs'), fvs) <- rnStmts (PatGuard ctxt) guards $
rnLExpr rhs
- ; checkM (pattern_guards_allowed || is_standard_guard guards')
+ ; unless (pattern_guards_allowed || is_standard_guard guards')
(addWarn (nonStdGuardErr guards'))
; return (GRHS guards' rhs', fvs) }
projects / ghc-hetmet.git / blobdiff