,("→", ITrarrow, unicodeSyntaxEnabled)
,("←", ITlarrow, unicodeSyntaxEnabled)
,("⋯", ITdotdot, unicodeSyntaxEnabled)
+
+ ,("⤙", ITlarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i)
+ ,("⤚", ITrarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i)
+ ,("⤛", ITLarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i)
+ ,("⤜", ITRarrowtail, \i -> unicodeSyntaxEnabled i && arrowsEnabled i)
+
+ ,("★", ITstar, unicodeSyntaxEnabled)
+
-- ToDo: ideally, → and ∷ should be "specials", so that they cannot
-- form part of a large operator. This would let us have a better
-- syntax for kinds: ɑ∷*→* would be a legal kind signature. (maybe).
setLine :: Int -> Action
setLine code span buf len = do
let line = parseUnsignedInteger buf len 10 octDecDigit
- setSrcLoc (mkSrcLoc (srcSpanFile span) (fromIntegral line - 1) 0)
+ setSrcLoc (mkSrcLoc (srcSpanFile span) (fromIntegral line - 1) 1)
-- subtract one: the line number refers to the *following* line
_ <- popLexState
pushLexState code
setFile :: Int -> Action
setFile code span buf len = do
let file = lexemeToFastString (stepOn buf) (len-2)
+ setAlrLastLoc noSrcSpan
setSrcLoc (mkSrcLoc file (srcSpanEndLine span) (srcSpanEndCol span))
_ <- popLexState
pushLexState code
return (L (mkSrcSpan loc end) (ITprimchar ch))
_other ->
return (L (mkSrcSpan loc end) (ITchar ch))
- else do
+ else do
return (L (mkSrcSpan loc end) (ITchar ch))
lex_char :: Char -> AlexInput -> P Char
context :: [LayoutContext],
lex_state :: [Int],
-- Used in the alternative layout rule:
+ -- These tokens are the next ones to be sent out. They are
+ -- just blindly emitted, without the rule looking at them again:
alr_pending_implicit_tokens :: [Located Token],
+ -- This is the next token to be considered or, if it is Nothing,
+ -- we need to get the next token from the input stream:
alr_next_token :: Maybe (Located Token),
+ -- This is what we consider to be the locatino of the last token
+ -- emitted:
alr_last_loc :: SrcSpan,
+ -- The stack of layout contexts:
alr_context :: [ALRContext],
+ -- Are we expecting a '{'? If it's Just, then the ALRLayout tells
+ -- us what sort of layout the '{' will open:
alr_expecting_ocurly :: Maybe ALRLayout
}
-- last_loc and last_len are used when generating error messages,
mExpectingOCurly <- getAlrExpectingOCurly
let thisLoc = getLoc t
thisCol = srcSpanStartCol thisLoc
- newLine = srcSpanStartLine thisLoc > srcSpanEndLine lastLoc
+ newLine = (lastLoc == noSrcSpan)
+ || (srcSpanStartLine thisLoc > srcSpanEndLine lastLoc)
case (unLoc t, context, mExpectingOCurly) of
+ -- This case handles a GHC extension to the original H98
+ -- layout rule...
+ (ITocurly, _, Just _) ->
+ do setAlrExpectingOCurly Nothing
+ setALRContext (ALRNoLayout (containsCommas ITocurly) : context)
+ return t
+ -- ...and makes this case unnecessary
+ {-
-- I think our implicit open-curly handling is slightly
-- different to John's, in how it interacts with newlines
-- and "in"
do setAlrExpectingOCurly Nothing
setNextToken t
lexTokenAlr
+ -}
(_, ALRLayout _ col : ls, Just expectingOCurly)
- | thisCol > col ->
+ | (thisCol > col) ||
+ (thisCol == col &&
+ isNonDecreasingIntentation expectingOCurly) ->
do setAlrExpectingOCurly Nothing
setALRContext (ALRLayout expectingOCurly thisCol : context)
setNextToken t
return (L thisLoc ITocurly)
| otherwise ->
do setAlrExpectingOCurly Nothing
- setPendingImplicitTokens [L thisLoc ITccurly]
+ setPendingImplicitTokens [L lastLoc ITccurly]
setNextToken t
- return (L thisLoc ITocurly)
+ return (L lastLoc ITocurly)
(_, _, Just expectingOCurly) ->
do setAlrExpectingOCurly Nothing
setALRContext (ALRLayout expectingOCurly thisCol : context)
do setPendingImplicitTokens [t]
setALRContext ls
return (L thisLoc ITccurly)
- (_, ls@(ALRLayout _ col : _), _)
- | newLine && thisCol <= col ->
- do let f ls'@(ALRLayout _ col' : ls'')
- | thisCol < col' = case f ls'' of
- (ts, ls''') ->
- (L thisLoc ITccurly : ts, ls''')
- | thisCol == col' = ([L thisLoc ITsemi], ls')
- | otherwise = ([], ls')
- f ls' = ([], ls')
- case f ls of
- (t' : ts, ls') ->
- do setALRContext ls'
- setPendingImplicitTokens ts
- setNextToken t
- return t'
- _ -> panic "Layout rule: [] when considering newline"
+ (_, ALRLayout _ col : ls, _)
+ | newLine && thisCol == col ->
+ do setNextToken t
+ return (L thisLoc ITsemi)
+ | newLine && thisCol < col ->
+ do setALRContext ls
+ setNextToken t
+ -- Note that we use lastLoc, as we may need to close
+ -- more layouts, or give a semicolon
+ return (L lastLoc ITccurly)
(u, _, _)
| isALRopen u ->
do setALRContext (ALRNoLayout (containsCommas u) : context)
do setALRContext ls
setPendingImplicitTokens [t]
return (L thisLoc ITccurly)
- (ITin, _ : ls, _) ->
+ (ITin, ALRLayout _ _ : ls, _) ->
do setALRContext ls
setNextToken t
return (L thisLoc ITccurly)
isALRclose ITcubxparen = True
isALRclose _ = False
+isNonDecreasingIntentation :: ALRLayout -> Bool
+isNonDecreasingIntentation ALRLayoutDo = True
+isNonDecreasingIntentation _ = False
+
containsCommas :: Token -> Bool
containsCommas IToparen = True
containsCommas ITobrack = True
+-- John doesn't have {} as containing commas, but records contain them,
+-- which caused a problem parsing Cabal's Distribution.Simple.InstallDirs
+-- (defaultInstallDirs).
+containsCommas ITocurly = True
-- GHC Extensions:
containsCommas IToubxparen = True
containsCommas _ = False
projects / ghc-hetmet.git / blobdiff