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This commit is contained in:
Rob Rix 2017-06-26 10:03:08 -04:00
parent ffe79d34c8
commit 10e81996fa
1 changed files with 1 additions and 4 deletions
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src/Data/Syntax/Assignment.hs
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@ -117,7 +117,6 @@ data AssignmentF ast grammar a where
Choose :: HasCallStack => IntMap.IntMap a -> AssignmentF ast grammar a
Many :: HasCallStack => Assignment ast grammar a -> AssignmentF ast grammar [a]
Alt :: HasCallStack => a -> a -> AssignmentF ast grammar a
Empty :: HasCallStack => AssignmentF ast grammar a
Throw :: HasCallStack => Error grammar -> AssignmentF ast grammar a
Catch :: HasCallStack => a -> (Error grammar -> a) -> AssignmentF ast grammar a
@ -296,14 +295,13 @@ makeState = AssignmentState 0 (Info.Pos 1 1)
instance Enum grammar => Alternative (Assignment ast grammar) where
empty :: HasCallStack => Assignment ast grammar a
empty = Empty `Then` return
empty = Choose mempty `Then` return
(<|>) :: HasCallStack => Assignment ast grammar a -> Assignment ast grammar a -> Assignment ast grammar a
Return a <|> _ = Return a
a <|> b | Just c <- (liftA2 (<>) `on` choices) a b = Choose c `Then` identity
| otherwise = wrap $ Alt a b
where choices :: Assignment ast grammar a -> Maybe (IntMap (Assignment ast grammar a))
choices (Choose choices `Then` continue) = Just (continue <$> choices)
choices (Empty `Then` _) = Just mempty
choices (Many rule `Then` continue) = fmap (const (Many rule `Then` continue)) <$> choices rule
choices _ = Nothing
many :: HasCallStack => Assignment ast grammar a -> Assignment ast grammar [a]
@ -318,7 +316,6 @@ instance Show grammar => Show1 (AssignmentF ast grammar) where
Choose choices -> showsUnaryWith (liftShowsPrec (liftShowsPrec sp sl) (liftShowList sp sl)) "Choose" d (IntMap.toList choices)
Many a -> showsUnaryWith (liftShowsPrec (\ d a -> sp d [a]) (sl . pure)) "Many" d a
Alt a b -> showsBinaryWith sp sp "Alt" d a b
Empty -> showString "Empty"
Throw e -> showsUnaryWith showsPrec "Throw" d e
Catch during handler -> showsBinaryWith sp (const (const (showChar '_'))) "Catch" d during handler