Text.Antlrc.Lexer

Documentation

newtype CommonToken

Lexer token struct.

Constructors

CommonToken (Ptr CommonToken)

newtype InputStream

Lexer input stream struct.

Constructors

InputStream (Ptr InputStream)

newtype Lexer

Lexer struct.

Constructors

Lexer (Ptr Lexer)

toInputStream :: Ptr InputStream -> InputStream

Cast from a pointer to an input stream to an input stream.

toCommonToken :: Ptr CommonToken -> CommonToken

Cast from a pointer to a token to a token.

fromCommonToken :: CommonToken -> Ptr b

Cast from a token to a pointer to a token.

lT :: Ptr InputStream -> Int -> IO (Ptr CommonToken)

Lookahead in the input stream at the token at the specified positive offset, where:

 LT input 1 

is the current token. Or a negative offset may be specified, where:

 LT input (-1) 

is the previous token.

 foreign export ccall isUnsignedInt :: Ptr InputStream -> IO Bool
 isUnsignedInt input =
   do token1 <- lT input 1 >>= tokenGetType
      if token1 /= UNSIGNED
        then return False
        else 
        do 
          token2 <- lT input 2 >>= tokenGetType
          return ((token2 /= CHAR) && (token2 /= SHORT) && (token2 /= LONG))

newtype AntlrString

Pointer to an ANTLR string.

Constructors

AntlrString (Ptr AntlrString)

fromAntlrString :: AntlrString -> Ptr b

Cast from an ANTLR string to a pointer to an ANTLR string.

tokenGetAntlrString :: Ptr CommonToken -> IO (Ptr AntlrString)

Obtain the token name ANTLR string for the specified token.

 tokenGetAntlrString token

For identifier tokens, the token string is interesting. For other tokens such as operator tokens, the token string is uninteresting, and may not be present, the token identifier enum should be used instead.

fromAntlrStringToMaybeString :: AntlrString -> IO (Maybe String)

Convert an ANTLR string to a Maybe String.

tokenGetTextMaybe :: Ptr CommonToken -> IO (Maybe String)

Obtain the token Maybe String for the specified token. For identifier tokens, the token string is interesting. For other tokens such as operator tokens, the token string is uninteresting, and may not be present, the token identifier enum should be used instead.

fromAntlrStringToString :: AntlrString -> IO String

Convert from an ANTLR string to a String. Note: the peekCStringLen function does not say what will happen if the C pointer is 0.

tokenGetText :: Ptr CommonToken -> IO String

Obtain the token String for the specified token. Note: the peekCStringLen function does not say what will happen if the C pointer is 0.

 foreign export ccall saIntV :: Ptr CommonToken -> IO (StablePtr TermInfo)
 saIntV token =
   do
     -- read the IntV integer value from the token text into n
     t <- tokenGetText token
     n <- readIO t
     -- obtain the source code line and charPosition from the token
     l <- tokenGetLine token
     c <- tokenGetCharPositionInLine token
     -- return the term, which is TmZero, or TmSucc TmZero, or TmSucc (TmSucc (...TmSucc TmZero))
     newStablePtr (intV (Info l c) n)

tokenGetType :: Enum e => Ptr CommonToken -> IO e

Obtain the token identifier for the specified token.

 foreign export ccall isInt :: Ptr InputStream -> IO Bool
 isInt input =
   do 
     token1 <- lT input 1 >>= tokenGetType
     return (token1 == INT)

tokenGetCharPositionInLine :: Ptr CommonToken -> IO Int

Obtain the character position in the source code line of where the token was read, for non-imaginary tokens.

 foreign export ccall saTrue :: Ptr CommonToken -> IO (StablePtr TermInfo)
 saTrue token =
   do
     -- obtain the source code line and charPosition from the token
     l <- tokenGetLine token
     c <- tokenGetCharPositionInLine token
     -- return the TmTrue term
     newStablePtr (TmTrue (Info l c))

tokenGetLine :: Ptr CommonToken -> IO Int

Obtain the the source code line of where the token was read, for non-imaginary tokens.

 foreign export ccall saFalse :: Ptr CommonToken -> IO (StablePtr TermInfo)
 saFalse token =
   do
     -- obtain the source code line and charPosition from the token
     l <- tokenGetLine token
     c <- tokenGetCharPositionInLine token
     -- return the TmFalse term
     newStablePtr (TmFalse (Info l c))

lT'_ :: InputStream -> CInt -> IO CommonToken

tokenGetAntlrString'_ :: CommonToken -> IO AntlrString