That's because \t is a regex metacharacter. If you only want to escape some metacharacters, you'll need to figure out which ones.

If you want to escape all metacharacters beside backslash, something like: 

  s/([^A-Za-z_0-9\\])/\\$1/g;

[download]
should do it.

In reply to Re: Re: Re: regex problem with metachars by sgifford
in thread regex problem with metachars by sweetblood

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