Are you forced to use a system grep without perl-compatible regex support? (i.e.- no "-P")

Let's say you want to grep a file for "foo", but not if it's proceeded by a comment "#" (with possible, legal leading whitespace). How would you grep for that on Unix with it's lame grep?

I turn to Perl. Can it be done without perl in one grep? Can this be done in Perl, but more simply? Show me!

Meanwhile, at the shell...

[[ "$( cat filename | perl -e 'print for grep { /^[[:space:]]{0,}#.+?f
+oo/ } <>' )" != "" ]] && found_but_commented=1;

[download]

I guess I'm looking for a re-usable perl-construct to use as a grep substitute. Something along those lines above. Is there anything more easy than | perl -e 'print for grep { /regex/ } <>


Tommy
A mistake can be valuable or costly, depending on how faithfully you pursue correction

In reply to Grep'ping on Unix without perl-compatible gnu grep - can you do it better? by Tommy

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