Hello.
Can anyone help me writing a parser for parsing a simplified
list of ABC fields (http://www.gre.ac.uk/~c.walshaw/abc/).
The grammar I want to test with is the following
------------------
file ::= *field
field ::= fieldA | fieldB
fieldA ::= "A:" text endOfLine
fieldB ::= "B:" text endOfLine restTextB
restTextB ::= (text endOfLine) 'not starting with "A:" or "B:"'
text ::= *(LETTER | DIGIT | SPACE | ":")
endOfLine ::= LF | CR LF
------------------
The parser I am trying:
------------------
file = many field
field = fieldA <|> fieldB
fieldA = do string "A:"
text
endOfLine
fieldB = do string "B:"
text
endOfLine
restTextB -- not starting with "A:" or "B:"
restTextB = do text
endOfLine
text = many (letter <|> digit <|> space <|> char ':')
endOfLine = string "\n" | string "\r\n"
------------------
Example of input:
------------------
A:1
B:Traditional
A:2
B:Line 1
Line 2
A Line 3
BBLine 4
A:3
------------------
Any sugestion on how to implement the 'not starting with
"A:" or "B:"' problem?
Romildo
--
Prof. José Romildo Malaquias
Departamento de Computação - Universidade Federal de Ouro Preto
http://www.decom.ufop.br/prof/romildo/ [EMAIL PROTECTED]
http://uber.com.br/romildo/ [EMAIL PROTECTED]
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