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RE: parser validation tools

  • Subject: RE: parser validation tools
  • From: "Bollinger, John Clayton" <jobollin@xxxxxxxxxxx>
  • Date: Thu, 11 May 2000 14:33:28 +0100 (BST)

> But in fact you need also to check that the hash isn't a legitimate
> character within a text string, e.g.  'this is a # legal data value'
> I offer as a challenge to anyone who is interested the problem of
> supplying a regexp that will definitely match a comment on a line.

Considering that you must also account for:

_illustrative_example
;
 This # symbol does not introduce a comment. 
;

I don't see how you can reliably identify comments with any regexp.
To do the job right it would appear that a lexical analyzer, e.g.
lex or flex, is in order.  Alternatively, such parsing could always
be written in any language and built into a special-purpose tool.


John Bollinger
Indiana University
Molecular Structure Center

jobollin@indiana.edu

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