in reply to Re: Unix 'grep -v' equivalency in Perl (was: Perl Regex Question)
in thread Unix 'grep -v' equivalency in Perl (was: Perl Regex Question)

To be more idiomatic, you should ensure that your @list doesn't contain anything that will get the regex bent out of shape. A simple application of quotemeta will help set things straight: 
my $re = join ("|", map {quotemeta} @list);
while (...)
{
     next if /$re/;
     print;
}

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I'm not a huge fan of the 'next LABEL' command. It's too much like 'goto', which is one of those things that shouldn't be shown in public.
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Re (tilly) 3: Unix 'grep -v' equivalency in Perl (was: Perl Regex Question)
by tilly (Archbishop) on Jul 10, 2001 at 01:31 UTC
    I don't think the purported similarity to goto is a good reason to not use Perl's loop control facilities. OK, the construct is abusable (what construct is not?), but when used appropriately I think that it clarifies things immensely.

    FWIW the following article on Loop Exits and Structured Programming helped shaped my thinking on this.

[reply]
      I agree. Consider the alternative (warning: marginally yucky code ahead):
      while (<INPUT>) {
 my $skip;
 for my $match (@list) {
  $skip = 1, last if /$match/;
 }
 next if $skip;
 print;
}

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[reply]
[d/l]
        Of course, you could always use grep in your grep equivalent: 
        foreach my $line (<INPUT>)
{
    next if (grep{$line =~ /\Q$_\E/}@list);
    print $line;
}

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[reply]
[d/l]

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