import {-# SOURCE #-} DsExpr ( dsExpr )
import HsSyn ( HsLit(..), OutPat(..), HsExpr(..) )
+import TcHsSyn ( TypecheckedPat )
import CoreSyn ( Expr(..), Bind(..) )
import Id ( Id )
import Literal ( mkMachInt, Literal(..) )
import Maybes ( catMaybes )
-import Type ( Type, isUnLiftedType )
+import Type ( isUnLiftedType )
import Panic ( panic, assertPanic )
\end{code}
where
match_prims_used _ [{-no more eqns-}] = returnDs []
- match_prims_used vars eqns_info@(EqnInfo n ctx ((LitPat literal lit_ty):ps1) _ : eqns)
+ match_prims_used vars eqns_info@(EqnInfo n ctx (pat@(LitPat literal lit_ty):ps1) _ : eqns)
= let
(shifted_eqns_for_this_lit, eqns_not_for_this_lit)
- = partitionEqnsByLit Nothing literal eqns_info
+ = partitionEqnsByLit pat eqns_info
in
-- recursive call to make other alts...
match_prims_used vars eqns_not_for_this_lit `thenDs` \ rest_of_alts ->
-- now do the business to make the alt for _this_ LitPat ...
match vars shifted_eqns_for_this_lit `thenDs` \ match_result ->
returnDs (
- (mk_core_lit lit_ty literal, match_result)
+ (mk_core_lit literal, match_result)
: rest_of_alts
)
where
- mk_core_lit :: Type -> HsLit -> Literal
-
- mk_core_lit ty (HsIntPrim i) = mkMachInt i
- mk_core_lit ty (HsCharPrim c) = MachChar c
- 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(isUnLiftedType ty)
- MachLitLit s ty
- mk_core_lit ty other = panic "matchLiterals:mk_core_lit:unhandled"
+ mk_core_lit :: HsLit -> Literal
+
+ mk_core_lit (HsIntPrim i) = mkMachInt i
+ mk_core_lit (HsCharPrim c) = MachChar c
+ mk_core_lit (HsStringPrim s) = MachStr s
+ mk_core_lit (HsFloatPrim f) = MachFloat f
+ mk_core_lit (HsDoublePrim d) = MachDouble d
+ mk_core_lit (HsLitLit s ty) = ASSERT(isUnLiftedType ty)
+ MachLitLit s ty
+ mk_core_lit 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)
+ eqns_info@(EqnInfo n ctx (pat@(NPat literal lit_ty eq_chk):ps1) _ : eqns)
= let
(shifted_eqns_for_this_lit, eqns_not_for_this_lit)
- = partitionEqnsByLit Nothing literal eqns_info
+ = partitionEqnsByLit pat eqns_info
in
dsExpr (HsApp eq_chk (HsVar var)) `thenDs` \ pred_expr ->
match vars shifted_eqns_for_this_lit `thenDs` \ inner_match_result ->
\begin{code}
-matchLiterals all_vars@(var:vars) eqns_info@(EqnInfo n ctx ((NPlusKPat master_n k ty ge sub):ps1) _ : eqns)
+matchLiterals all_vars@(var:vars) eqns_info@(EqnInfo n ctx (pat@(NPlusKPat master_n k ty ge sub):ps1) _ : eqns)
= let
(shifted_eqns_for_this_lit, eqns_not_for_this_lit)
- = partitionEqnsByLit (Just master_n) k eqns_info
+ = partitionEqnsByLit pat eqns_info
in
match vars shifted_eqns_for_this_lit `thenDs` \ inner_match_result ->
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
- -- is the "master" variable;
- -- Nothing for NPats and LitPats
- -> HsLit
+partitionEqnsByLit :: TypecheckedPat
-> [EquationInfo]
-> ([EquationInfo], -- These ones are for this lit, AND
-- they've been "shifted" by stripping
-- are exactly as fed in.
)
-partitionEqnsByLit nPlusK lit eqns
+partitionEqnsByLit master_pat eqns
= ( \ (xs,ys) -> (catMaybes xs, catMaybes ys))
- (unzip (map (partition_eqn nPlusK lit) eqns))
+ (unzip (map (partition_eqn master_pat) eqns))
where
- partition_eqn :: Maybe Id -> HsLit -> EquationInfo ->
- (Maybe EquationInfo, Maybe EquationInfo)
+ partition_eqn :: TypecheckedPat -> EquationInfo -> (Maybe EquationInfo, Maybe EquationInfo)
- partition_eqn Nothing lit (EqnInfo n ctx (LitPat k _ : remaining_pats) match_result)
- | lit `eq_lit` k = (Just (EqnInfo n ctx remaining_pats match_result), Nothing)
+ partition_eqn (LitPat k1 _) (EqnInfo n ctx (LitPat k2 _ : remaining_pats) match_result)
+ | k1 == k2 = (Just (EqnInfo n ctx remaining_pats match_result), Nothing)
-- NB the pattern is stripped off the EquationInfo
- partition_eqn Nothing lit (EqnInfo n ctx (NPat k _ _ : remaining_pats) match_result)
- | lit `eq_lit` k = (Just (EqnInfo n ctx remaining_pats match_result), Nothing)
+ partition_eqn (NPat k1 _ _) (EqnInfo n ctx (NPat k2 _ _ : remaining_pats) match_result)
+ | k1 == k2 = (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)
- | lit `eq_lit` k = (Just (EqnInfo n ctx remaining_pats new_match_result), Nothing)
+ partition_eqn (NPlusKPat master_n k1 _ _ _)
+ (EqnInfo n ctx (NPlusKPat n' k2 _ _ _ : remaining_pats) match_result)
+ | k1 == k2 = (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
+ [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)
+ partition_eqn master_pat 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
- partition_eqn nPlusK lit eqn = (Nothing, Just eqn)
-
--- ToDo: meditate about this equality business...
-
-eq_lit (HsInt i1) (HsInt i2) = i1 == i2
-eq_lit (HsFrac f1) (HsFrac f2) = f1 == f2
-
-eq_lit (HsIntPrim i1) (HsIntPrim i2) = i1 == i2
-eq_lit (HsFloatPrim f1) (HsFloatPrim f2) = f1 == f2
-eq_lit (HsDoublePrim d1) (HsDoublePrim d2) = d1 == d2
-eq_lit (HsChar c1) (HsChar c2) = c1 == c2
-eq_lit (HsCharPrim c1) (HsCharPrim c2) = c1 == c2
-eq_lit (HsString s1) (HsString s2) = s1 == s2
-eq_lit (HsStringPrim s1) (HsStringPrim s2) = s1 == s2
-eq_lit (HsLitLit s1) (HsLitLit s2) = s1 == s2 -- ToDo: ??? (dubious)
-eq_lit other1 other2 = panic "matchLiterals:eq_lit"
+ partition_eqn master_pat eqn = (Nothing, Just eqn)
\end{code}