The Regex Story

Lie Ryan lie.1296 at gmail.com
Fri Apr 9 06:48:22 CEST 2010


On 04/09/10 12:32, Dotan Cohen wrote:
>> Regexes do have their uses. It's a case of knowing when they are the
>> best approach and when they aren't.
> 
> Agreed. The problems begin when the "when they aren't" is not recognised.

But problems also arises when people are suggesting overly complex
series of built-in functions for what is better handled by regex.

Using built-in functions (to me at least) is not a  natural way to match
strings, and makes things less understandable for anything but very
simple manipulations. Regex is like Query-by-Example (QBE), in database,
you give an example and you get a result; you give the general pattern
and you get a match. Regex is declarative similar to full-blown parser,
instead of procedural like built-in functions. Regex's unsuitability for
complex parsing stems from terseness and inability to handle arbitrary
nests.

People need to recognize when built-in function isn't suitable and when
bringing forth pyparsing for parsing one or two is just an overkill.

Unreasonable phobia to regex is just as much harmful as overuse of it.



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