I would argue against doing this with a regex. When you have something that is known to conform to a standard, like URIs or HTML, better to use a parser. It's easier to adapt, easier to extend use cases, immune to argument order, and generally more likely to be bomb-proof.

How about this for your thing. 

use URI::QueryParam; # introduces a new method to URI

sub test_url {
    my ( $uri, $server ) = @_;
    # returns true, ok to index/spider
    # return false, don't index or spider

    # A white list is always better than
    # a black list if you can make one
    return unless $uri->path =~ /\.html$/;

    # Note about what this condition really means
    return if
      $uri->query_param("C") eq "N"
          and
      $uri->query_param("O") eq "D";

    # Note about what this condition really means
    return if
      $uri->query_param("C") eq "M"
          and
      $uri->query_param("O") eq "A";

    # make sure that the path is limited to the docs path
    return $uri->path =~ m[^/starteam_area/];
}

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In reply to Re: Difficult? regex by Your Mother
in thread Difficult? regex by Anonymous Monk

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