in reply to Validating a Regexp

sub is_valid_re {
    eval { qr/$_[0]/ };
    return $@ ? 'NO' : 'YES';
}

my @regexes = qw(a[hjg].* *a[hj);
print is_valid_re($_), $/ for @regexes;

__output__

YES
NO

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That seems to do the job.
HTH

_________
broquaint

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Re: Re: Validating a Regexp
by Juerd (Abbot) on Jul 29, 2002 at 17:46 UTC 

    sub is_valid_re {
    eval { qr/$_[0]/ };
    return $@ ? 'NO' : 'YES';
}

    [download]

    This eval returns a regex or undef, so you could write as follows: 

    sub is_valid_re { eval { qr/$_[0] } ? 'YES' : 'NO' }

    [download]
    But I'd _never_ return words when a boolean value is needed. Digits are so much nicer for that. If you want words, you could create yet another sub to turn the truth number into a word. 
    sub is_valid_re { eval { qr/$_[0] } }
print is_valid_re('abc') ? 'YES' : 'NO';

sub human_bool { shift ? 'YES' : 'NO' }
print human_bool(is_valid_re('abc'));

    [download]

    - Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

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