%
-% (c) The GRASP/AQUA Project, Glasgow University, 1992-1996
+% (c) The GRASP/AQUA Project, Glasgow University, 1992-1998
%
\section[MatchLit]{Pattern-matching literal patterns}
import {-# SOURCE #-} Match ( match )
import {-# SOURCE #-} DsExpr ( dsExpr )
-import HsSyn ( HsLit(..), OutPat(..), HsExpr(..), Fixity,
- Match, HsBinds, DoOrListComp, HsType, ArithSeqInfo )
+import HsSyn ( HsLit(..), OutPat(..), HsExpr(..) )
import TcHsSyn ( TypecheckedHsExpr, TypecheckedPat )
-import CoreSyn ( CoreExpr, CoreBinding, GenCoreExpr(..), GenCoreBinding(..) )
-import Id ( GenId {- instance Eq -}, Id )
+import CoreSyn ( Expr(..), Bind(..) )
+import Id ( Id )
import DsMonad
import DsUtils
import Literal ( mkMachInt, Literal(..) )
+import PrimRep ( PrimRep(IntRep) )
import Maybes ( catMaybes )
-import Type ( Type )
-import Util ( panic, assertPanic )
+import Type ( Type, isUnLiftedType )
+import Panic ( panic, assertPanic )
\end{code}
\begin{code}
match_prims_used vars eqns_info `thenDs` \ prim_alts ->
-- MAKE THE PRIMITIVE CASE
- mkCoPrimCaseMatchResult var prim_alts
+ returnDs (mkCoPrimCaseMatchResult var prim_alts)
where
match_prims_used _ [{-no more eqns-}] = returnDs []
mk_core_lit ty (HsStringPrim s) = MachStr s
mk_core_lit ty (HsFloatPrim f) = MachFloat f
mk_core_lit ty (HsDoublePrim d) = MachDouble d
- mk_core_lit ty (HsLitLit s) = ASSERT(isUnpointedType ty)
- MachLitLit s (panic "MatchLit.matchLiterals:mk_core_lit:HsLitLit; typePrimRep???")
+ mk_core_lit ty (HsLitLit s) = ASSERT(isUnLiftedType ty)
+ MachLitLit s ty
mk_core_lit ty other = panic "matchLiterals:mk_core_lit:unhandled"
\end{code}
\begin{code}
-matchLiterals all_vars@(var:vars) eqns_info@(EqnInfo n ctx ((NPat literal lit_ty eq_chk):ps1) _ : eqns)
+matchLiterals all_vars@(var:vars)
+ eqns_info@(EqnInfo n ctx ((NPat literal lit_ty eq_chk):ps1) _ : eqns)
= let
(shifted_eqns_for_this_lit, eqns_not_for_this_lit)
= partitionEqnsByLit Nothing literal eqns_info
in
- dsExpr (HsApp eq_chk (HsVar var)) `thenDs` \ pred_expr ->
- match vars shifted_eqns_for_this_lit `thenDs` \ inner_match_result ->
- mkGuardedMatchResult pred_expr inner_match_result `thenDs` \ match_result1 ->
-
+ dsExpr (HsApp eq_chk (HsVar var)) `thenDs` \ pred_expr ->
+ match vars shifted_eqns_for_this_lit `thenDs` \ inner_match_result ->
+ let
+ match_result1 = mkGuardedMatchResult pred_expr inner_match_result
+ in
if (null eqns_not_for_this_lit)
then
returnDs match_result1
else
matchLiterals all_vars eqns_not_for_this_lit `thenDs` \ match_result2 ->
- combineMatchResults match_result1 match_result2
+ returnDs (combineMatchResults match_result1 match_result2)
\end{code}
For an n+k pattern, we use the various magic expressions we've been given.
dsExpr (HsApp ge (HsVar var)) `thenDs` \ ge_expr ->
dsExpr (HsApp sub (HsVar var)) `thenDs` \ nminusk_expr ->
- mkGuardedMatchResult
- ge_expr
- (mkCoLetsMatchResult [NonRec master_n nminusk_expr] inner_match_result)
- `thenDs` \ match_result1 ->
-
+ let
+ match_result1 = mkGuardedMatchResult ge_expr $
+ mkCoLetsMatchResult [NonRec master_n nminusk_expr] $
+ inner_match_result
+ in
if (null eqns_not_for_this_lit)
then
returnDs match_result1
else
matchLiterals all_vars eqns_not_for_this_lit `thenDs` \ match_result2 ->
- combineMatchResults match_result1 match_result2
+ returnDs (combineMatchResults match_result1 match_result2)
\end{code}
-Given a blob of LitPats/NPats, we want to split them into those
+Given a blob of @LitPat@s/@NPat@s, we want to split them into those
that are ``same''/different as one we are looking at. We need to know
-whether we're looking at a LitPat/NPat, and what literal we're after.
+whether we're looking at a @LitPat@/@NPat@, and what literal we're after.
\begin{code}
partitionEqnsByLit :: Maybe Id -- (Just v) for N-plus-K patterns, where v
| lit `eq_lit` k = (Just (EqnInfo n ctx remaining_pats match_result), Nothing)
-- NB the pattern is stripped off the EquationInfo
- partition_eqn (Just master_n) lit (EqnInfo n ctx (NPlusKPat n' k _ _ _ : remaining_pats) match_result)
+ partition_eqn (Just master_n) lit
+ (EqnInfo n ctx (NPlusKPat n' k _ _ _ : remaining_pats) match_result)
| lit `eq_lit` k = (Just (EqnInfo n ctx remaining_pats new_match_result), Nothing)
-- NB the pattern is stripped off the EquationInfo
where
new_match_result | master_n == n' = match_result
- | otherwise = mkCoLetsMatchResult [NonRec n' (Var master_n)] match_result
+ | otherwise = mkCoLetsMatchResult
+ [NonRec n' (Var master_n)] match_result
- -- Wild-card patterns, which will only show up in the shadows, go into both groups
- partition_eqn nPlusK lit eqn@(EqnInfo n ctx (WildPat _ : remaining_pats) match_result)
+ -- Wild-card patterns, which will only show up in the shadows,
+ -- go into both groups
+ partition_eqn nPlusK lit
+ eqn@(EqnInfo n ctx (WildPat _ : remaining_pats) match_result)
= (Just (EqnInfo n ctx remaining_pats match_result), Just eqn)
-- Default case; not for this pattern
projects / ghc-hetmet.git / blobdiff