grep in Perl is essentially a simple method for filtering a list. I tend to recommend avoiding it while you are still familiarizing yourself with Perl's constructs.

grep allows you to accomplish something like: 

my @second;
for my $element (@first) {
    push @second, $element if condition($element);
}

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in a concise syntax. Simple filtering by a regular expression is a classic use case. If you have side effects or complex tests, then grep may be a bad choice.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re^3: CGI Help by kennethk
in thread CGI Help by phizymonk

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