What is the efficient way to find some pattern in a big text?

Posted by salman on Stack Overflow See other posts from Stack Overflow or by salman
Published on 2010-05-12T06:03:38Z Indexed on 2010/05/12 7:44 UTC
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I want to extract email addresses from a large text file. what is the best way to do it?

My idea is to find '@' in the text and use "Regex" to find email address into substring at (for example) 256 chars before this position and length of 512.

P.S.: Straightforwardly I want to know the best and most efficient way to find some pattern (like email addresses) in a huge text.

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