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authorVladislav Zavialov <vlad.z.4096@gmail.com>2018-06-14 15:02:36 -0400
committerRichard Eisenberg <rae@cs.brynmawr.edu>2018-06-14 15:05:32 -0400
commitd650729f9a0f3b6aa5e6ef2d5fba337f6f70fa60 (patch)
treeac224609397d4b7ca7072fc87739d2522be7675b /compiler/parser/Parser.y
parent4672e2ebf040feffde4e7e2d79c479e4c0c3efaf (diff)
downloadhaskell-d650729f9a0f3b6aa5e6ef2d5fba337f6f70fa60.tar.gz
Embrace -XTypeInType, add -XStarIsType
Summary: Implement the "Embrace Type :: Type" GHC proposal, .../ghc-proposals/blob/master/proposals/0020-no-type-in-type.rst GHC 8.0 included a major change to GHC's type system: the Type :: Type axiom. Though casual users were protected from this by hiding its features behind the -XTypeInType extension, all programs written in GHC 8+ have the axiom behind the scenes. In order to preserve backward compatibility, various legacy features were left unchanged. For example, with -XDataKinds but not -XTypeInType, GADTs could not be used in types. Now these restrictions are lifted and -XTypeInType becomes a redundant flag that will be eventually deprecated. * Incorporate the features currently in -XTypeInType into the -XPolyKinds and -XDataKinds extensions. * Introduce a new extension -XStarIsType to control how to parse * in code and whether to print it in error messages. Test Plan: Validate Reviewers: goldfire, hvr, bgamari, alanz, simonpj Reviewed By: goldfire, simonpj Subscribers: rwbarton, thomie, mpickering, carter GHC Trac Issues: #15195 Differential Revision: https://phabricator.haskell.org/D4748
Diffstat (limited to 'compiler/parser/Parser.y')
-rw-r--r--compiler/parser/Parser.y88
1 files changed, 44 insertions, 44 deletions
diff --git a/compiler/parser/Parser.y b/compiler/parser/Parser.y
index 25edb3e591..c1ee8a4855 100644
--- a/compiler/parser/Parser.y
+++ b/compiler/parser/Parser.y
@@ -88,7 +88,7 @@ import GhcPrelude
import qualified GHC.LanguageExtensions as LangExt
}
-%expect 233 -- shift/reduce conflicts
+%expect 235 -- shift/reduce conflicts
{- Last updated: 04 June 2018
@@ -158,7 +158,7 @@ Shift parses as (per longest-parse rule):
-------------------------------------------------------------------------------
-state 143 contains 14 shift/reduce conflicts.
+state 144 contains 15 shift/reduce conflicts.
exp -> infixexp . '::' sigtype
exp -> infixexp . '-<' exp
@@ -169,7 +169,7 @@ state 143 contains 14 shift/reduce conflicts.
infixexp -> infixexp . qop exp10
Conflicts: ':' '::' '-' '!' '-<' '>-' '-<<' '>>-'
- '.' '`' VARSYM CONSYM QVARSYM QCONSYM
+ '.' '`' '*' VARSYM CONSYM QVARSYM QCONSYM
Examples of ambiguity:
'if x then y else z -< e'
@@ -183,7 +183,7 @@ Shift parses as (per longest-parse rule):
-------------------------------------------------------------------------------
-state 148 contains 68 shift/reduce conflicts.
+state 149 contains 67 shift/reduce conflicts.
*** exp10 -> fexp .
fexp -> fexp . aexp
@@ -201,7 +201,7 @@ Shift parses as (per longest-parse rule):
-------------------------------------------------------------------------------
-state 204 contains 28 shift/reduce conflicts.
+state 204 contains 27 shift/reduce conflicts.
aexp2 -> TH_TY_QUOTE . tyvar
aexp2 -> TH_TY_QUOTE . gtycon
@@ -220,7 +220,7 @@ Shift parses as (per longest-parse rule):
-------------------------------------------------------------------------------
-state 308 contains 1 shift/reduce conflicts.
+state 300 contains 1 shift/reduce conflicts.
rule -> STRING . rule_activation rule_forall infixexp '=' exp
@@ -238,7 +238,7 @@ a rule instructing how to rewrite the expression '[0] f'.
-------------------------------------------------------------------------------
-state 318 contains 1 shift/reduce conflict.
+state 310 contains 1 shift/reduce conflict.
*** type -> btype .
type -> btype . '->' ctype
@@ -249,7 +249,7 @@ Same as state 61 but without contexts.
-------------------------------------------------------------------------------
-state 362 contains 1 shift/reduce conflicts.
+state 354 contains 1 shift/reduce conflicts.
tup_exprs -> commas . tup_tail
sysdcon_nolist -> '(' commas . ')'
@@ -264,7 +264,7 @@ if -XTupleSections is not specified.
-------------------------------------------------------------------------------
-state 418 contains 1 shift/reduce conflicts.
+state 409 contains 1 shift/reduce conflicts.
tup_exprs -> commas . tup_tail
sysdcon_nolist -> '(#' commas . '#)'
@@ -272,21 +272,21 @@ state 418 contains 1 shift/reduce conflicts.
Conflict: '#)' (empty tup_tail reduces)
-Same as State 362 for unboxed tuples.
+Same as State 354 for unboxed tuples.
-------------------------------------------------------------------------------
-state 429 contains 68 shift/reduce conflicts.
+state 417 contains 67 shift/reduce conflicts.
*** exp10 -> '-' fexp .
fexp -> fexp . aexp
fexp -> fexp . TYPEAPP atype
-Same as 148 but with a unary minus.
+Same as 149 but with a unary minus.
-------------------------------------------------------------------------------
-state 493 contains 1 shift/reduce conflict.
+state 481 contains 1 shift/reduce conflict.
oqtycon -> '(' qtyconsym . ')'
*** qtyconop -> qtyconsym .
@@ -300,7 +300,7 @@ parenthesized infix type expression of length 1.
-------------------------------------------------------------------------------
-state 694 contains 1 shift/reduce conflicts.
+state 675 contains 1 shift/reduce conflicts.
*** aexp2 -> ipvar .
dbind -> ipvar . '=' exp
@@ -315,7 +315,7 @@ sensible meaning, namely the lhs of an implicit binding.
-------------------------------------------------------------------------------
-state 771 contains 1 shift/reduce conflicts.
+state 752 contains 1 shift/reduce conflicts.
rule -> STRING rule_activation . rule_forall infixexp '=' exp
@@ -332,7 +332,7 @@ doesn't include 'forall'.
-------------------------------------------------------------------------------
-state 1019 contains 1 shift/reduce conflicts.
+state 986 contains 1 shift/reduce conflicts.
transformqual -> 'then' 'group' . 'using' exp
transformqual -> 'then' 'group' . 'by' exp 'using' exp
@@ -342,7 +342,7 @@ state 1019 contains 1 shift/reduce conflicts.
-------------------------------------------------------------------------------
-state 1404 contains 1 shift/reduce conflict.
+state 1367 contains 1 shift/reduce conflict.
*** atype -> tyvar .
tv_bndr -> '(' tyvar . '::' kind ')'
@@ -526,6 +526,7 @@ are the most common patterns, rewritten as regular expressions for clarity:
'=>' { L _ (ITdarrow _) }
'-' { L _ ITminus }
'!' { L _ ITbang }
+ '*' { L _ (ITstar _) }
'-<' { L _ (ITlarrowtail _) } -- for arrow notation
'>-' { L _ (ITrarrowtail _) } -- for arrow notation
'-<<' { L _ (ITLarrowtail _) } -- for arrow notation
@@ -1160,11 +1161,7 @@ deriv_strategy_no_via :: { LDerivStrategy GhcPs }
[mj AnnNewtype $1] }
deriv_strategy_via :: { LDerivStrategy GhcPs }
- : 'via' tyapp {% splitTildeApps [$2] >>= \tys -> let
- ty :: LHsType GhcPs
- ty = sL1 $1 $ mkHsAppsTy tys
-
- in ams (sLL $1 $> (ViaStrategy (mkLHsSigType ty)))
+ : 'via' type {% ams (sLL $1 $> (ViaStrategy (mkLHsSigType $2)))
[mj AnnVia $1] }
deriv_standalone_strategy :: { Maybe (LDerivStrategy GhcPs) }
@@ -1856,7 +1853,7 @@ context :: { LHsContext GhcPs }
} }
context_no_ops :: { LHsContext GhcPs }
- : btype_no_ops {% do { ty <- splitTilde $1
+ : btype_no_ops {% do { ty <- splitTilde (reverse (unLoc $1))
; (anns,ctx) <- checkContext ty
; if null (unLoc ctx)
then addAnnotation (gl ty) AnnUnit (gl ty)
@@ -1911,29 +1908,27 @@ typedoc :: { LHsType GhcPs }
-- See Note [Parsing ~]
btype :: { LHsType GhcPs }
- : tyapps {% splitTildeApps (reverse (unLoc $1)) >>=
- \ts -> return $ sL1 $1 $ mkHsAppsTy ts }
+ : tyapps {% mergeOps (unLoc $1) }
-- Used for parsing Haskell98-style data constructors,
-- in order to forbid the blasphemous
-- > data Foo = Int :+ Char :* Bool
-- See also Note [Parsing data constructors is hard] in RdrHsSyn
-btype_no_ops :: { LHsType GhcPs }
- : btype_no_ops atype_docs { sLL $1 $> $ HsAppTy noExt $1 $2 }
- | atype_docs { $1 }
+btype_no_ops :: { Located [LHsType GhcPs] } -- NB: This list is reversed
+ : atype_docs { sL1 $1 [$1] }
+ | btype_no_ops atype_docs { sLL $1 $> $ $2 : (unLoc $1) }
-tyapps :: { Located [LHsAppType GhcPs] } -- NB: This list is reversed
+tyapps :: { Located [Located TyEl] } -- NB: This list is reversed
: tyapp { sL1 $1 [$1] }
| tyapps tyapp { sLL $1 $> $ $2 : (unLoc $1) }
--- See Note [HsAppsTy] in HsTypes
-tyapp :: { LHsAppType GhcPs }
- : atype { sL1 $1 $ HsAppPrefix noExt $1 }
- | qtyconop { sL1 $1 $ HsAppInfix noExt $1 }
- | tyvarop { sL1 $1 $ HsAppInfix noExt $1 }
- | SIMPLEQUOTE qconop {% ams (sLL $1 $> $ HsAppInfix noExt $2)
+tyapp :: { Located TyEl }
+ : atype { sL1 $1 $ TyElOpd (unLoc $1) }
+ | qtyconop { sL1 $1 $ TyElOpr (unLoc $1) }
+ | tyvarop { sL1 $1 $ TyElOpr (unLoc $1) }
+ | SIMPLEQUOTE qconop {% ams (sLL $1 $> $ TyElOpr (unLoc $2))
[mj AnnSimpleQuote $1] }
- | SIMPLEQUOTE varop {% ams (sLL $1 $> $ HsAppInfix noExt $2)
+ | SIMPLEQUOTE varop {% ams (sLL $1 $> $ TyElOpr (unLoc $2))
[mj AnnSimpleQuote $1] }
atype_docs :: { LHsType GhcPs }
@@ -1943,6 +1938,8 @@ atype_docs :: { LHsType GhcPs }
atype :: { LHsType GhcPs }
: ntgtycon { sL1 $1 (HsTyVar noExt NotPromoted $1) } -- Not including unit tuples
| tyvar { sL1 $1 (HsTyVar noExt NotPromoted $1) } -- (See Note [Unit tuples])
+ | '*' {% do { warnStarIsType (getLoc $1)
+ ; return $ sL1 $1 (HsStarTy noExt (isUnicode $1)) } }
| strict_mark atype {% ams (sLL $1 $> (HsBangTy noExt (snd $ unLoc $1) $2))
(fst $ unLoc $1) } -- Constructor sigs only
| '{' fielddecls '}' {% amms (checkRecordSyntax
@@ -2061,13 +2058,13 @@ Note [Parsing ~]
Due to parsing conflicts between laziness annotations in data type
declarations (see strict_mark) and equality types ~'s are always
-parsed as laziness annotations, and turned into HsEqTy's in the
+parsed as laziness annotations, and turned into HsOpTy's in the
correct places using RdrHsSyn.splitTilde.
Since strict_mark is parsed as part of atype which is part of type,
typedoc and context (where HsEqTy previously appeared) it made most
sense and was simplest to parse ~ as part of strict_mark and later
-turn them into HsEqTy's.
+turn them into HsOpTy's.
-}
@@ -2191,14 +2188,15 @@ forall :: { Located ([AddAnn], Maybe [LHsTyVarBndr GhcPs]) }
constr_stuff :: { Located (Located RdrName, HsConDeclDetails GhcPs, Maybe LHsDocString) }
-- See Note [Parsing data constructors is hard] in RdrHsSyn
- : btype_no_ops {% do { c <- splitCon $1
- ; return $ sLL $1 $> c } }
+ : btype_no_ops {% do { c <- splitCon (unLoc $1)
+ ; return $ sL1 $1 c } }
| btype_no_ops conop maybe_docprev btype_no_ops
- {% do { lhs <- splitTilde $1
- ; (_, ds_l) <- checkInfixConstr lhs
- ; (rhs, ds_r) <- checkInfixConstr $4
+ {% do { lhs <- splitTilde (reverse (unLoc $1))
+ ; (_, ds_l) <- checkInfixConstr lhs
+ ; let rhs1 = foldl1 mkHsAppTy (reverse (unLoc $4))
+ ; (rhs, ds_r) <- checkInfixConstr rhs1
; return $ if isJust (ds_l `mplus` $3)
- then sLL $1 $> ($2, InfixCon lhs $4, $3)
+ then sLL $1 $> ($2, InfixCon lhs rhs1, $3)
else sLL $1 $> ($2, InfixCon lhs rhs, ds_r) } }
fielddecls :: { [LConDeclField GhcPs] }
@@ -3370,6 +3368,7 @@ special_id
special_sym :: { Located FastString }
special_sym : '!' {% ams (sL1 $1 (fsLit "!")) [mj AnnBang $1] }
| '.' { sL1 $1 (fsLit ".") }
+ | '*' { sL1 $1 (fsLit (if isUnicode $1 then "★" else "*")) }
-----------------------------------------------------------------------------
-- Data constructors
@@ -3552,6 +3551,7 @@ isUnicode (L _ (IToparenbar iu)) = iu == UnicodeSyntax
isUnicode (L _ (ITcparenbar iu)) = iu == UnicodeSyntax
isUnicode (L _ (ITopenExpQuote _ iu)) = iu == UnicodeSyntax
isUnicode (L _ (ITcloseQuote iu)) = iu == UnicodeSyntax
+isUnicode (L _ (ITstar iu)) = iu == UnicodeSyntax
isUnicode _ = False
hasE :: Located Token -> Bool
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