Character classes like [ABCD] can be converted to alternation as follows: 
my $class = 'ABCD';
my $xerox = join '|', split //, $class;  # create alternation
$xerox = '(?:' . $xerox . ')';  # non-capturing grouping

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-Mark

In reply to Re: regular expression-xerox by kvale
in thread regular expression-xerox by oz

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