lexers vs parsers

Posted by Naveen on Stack Overflow See other posts from Stack Overflow or by Naveen
Published on 2010-05-16T06:47:38Z Indexed on 2010/05/17 6:40 UTC
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antlr

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lexer

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parser

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pygments

Are lexers and parsers really that different in theory ?

It seems fashionable to hate regular expressions: coding horror, another blog post.

However, popular lexing based tools: pygments, geshi, or prettify, all use regular expressions. They seem to lex anything...

When is lexing enough, when do you need EBNF ?

Has anyone used the tokens produced by these lexers with bison or antlr parser generators?

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