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Something parses!

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This commit is contained in:
Adam Wick
2016-06-08 16:12:43 -04:00
parent 12ef49fc7b
commit e5bb88aa4e
9 changed files with 294 additions and 628 deletions
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23
src/Bang/Syntax/Lexer.x
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@@ -10,6 +10,7 @@ import Bang.Syntax.Location
import Bang.Syntax.Name
import Bang.Syntax.Token
import Data.Char(isSpace, isAscii, ord)
import Data.Int(Int64)
import Data.Maybe(fromMaybe)
import Data.Text.Lazy(Text)
import qualified Data.Text.Lazy as T
@@ -34,13 +35,13 @@ $escape_char = [abfnrtv'\"\\]
-- Whitespace
$white+ ;
"/*".*"*/" ;
"/*"[.\n]*"*/" ;
-- Numbers
$decdigit+ { emitS (IntTok 10) }
"0x"$hexdigit+ { emitS (IntTok 16) }
"0o"$octdigit+ { emitS (IntTok 8) }
"0b"$bindigit+ { emitS (IntTok 2) }
$decdigit+ { emitI 0 (IntTok 10) }
"0x"$hexdigit+ { emitI 2 (IntTok 16) }
"0o"$octdigit+ { emitI 2 (IntTok 8) }
"0b"$bindigit+ { emitI 2 (IntTok 2) }
$decdigit+"."$decdigit+ ("e""-"?$decdigit+)? { emitS FloatTok}
$decdigit+"e""-"?$decdigit+ { emitS FloatTok}
@@ -74,7 +75,9 @@ lexer src mbPos txt = go (AlexInput startPos txt)
startPos = fromMaybe initialPosition mbPos
go input =
case alexScan input 0 of
AlexEOF -> []
AlexEOF -> let AlexInput pos _ = input
loc = Location src pos pos
in [EOFTok `locatedAt` loc]
AlexError input' -> let AlexInput pos text = input'
(as, bs) = T.break isSpace text
pos' = advanceWith' pos as
@@ -106,4 +109,12 @@ emitS mk src len (AlexInput pos t) = token `locatedAt` loc
token = mk txt
loc = Location src pos (pos `advanceWith'` txt)
emitI :: Int64 -> (Text -> Token) -> AlexAction
emitI dropCount mk src len (AlexInput pos t) = token `locatedAt` loc
where
baseText = T.take (fromIntegral len) t
txt = T.drop dropCount baseText
token = mk txt
loc = Location src pos (pos `advanceWith'` baseText)
}