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`grep' in Perl is a misnomer; it's not inherently related to RExen. It should really be named `filter' or something similar. As such, using a bare variable as the `EXPR' in grep EXPR, LIST won't invoke the REx engine at all -- basically you're checking $searchtext for truth each time through the `LIST', which is most certainly not WYM.

My personal vote on this problem would be to provide the users a radio button group allowing them to choose whether they want to use Perl-based or standard search-engine searches, rather than trying to come up with a heuristic to determine if $searchtext is a Perl REx or just a term.

However, if you really want to do that, you'll want to look into `\Q' and `\E' to quote characters in a REx, rather than going to all that trouble (on line 4) to take care of metacharacters. I'm skeptical of the conversion from `*' to `\w*', but I suppose it's a sensible choice.

Rather than trying to build up a string that syntactically resembles a REx in Perl code, build the actual search pattern and then use it in the grep inside of a REx:

grep m/$searchtext/, <STUFF>

You might also want to look into qr// for a more efficient and cleaner way to build RExen programatically.

-dlc


In reply to Re: How can grep search based on text or pattern based on user input? by dchetlin
in thread How can grep search based on text or pattern based on user input? by Russ

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