I want to know whether a numeric \x escape can be used to represent a character with a codepoint from U+0080 to U+00ff within a regular-expression character class.

In the code below, the pattern is intended to match any character in the 2-character range from U+007f to U+0080. The string doesn't contain either of those characters, so I expect the match to fail, but instead it succeeds.

The output is: "Your string is matched by /[\7f-\x80]/"


#!/usr/bin/perl -w

use warnings 'FATAL', 'all';
# Make every warning fatal.

use strict;
# Require strict checking of variable references, etc.

use utf8;
# Treat this script as encoded with UTF-8.

my $_ = 'abcdefg';
# Identify a string.

print 'Your string is ', (/[\7f-\x80]/ ? '' : 'NOT '),
    'matched by /[\7f-\x80]/', "\n";
# Report the result.

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Original content restored by GrandFather

In reply to \x in RE character class (deleted) by pool

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