NAME
Perl::Critic::Policy::Plicease::ProhibitUnicodeDigitInRegexp - Prohibit non-ASCII \d in regular expressions
VERSION
version 0.07
SYNOPSIS
perlcriticrc:
[Plicease::ProhibitUnicodeDigitInRegexp]
code:
/\d/; # not ok
/[0-9]/; # ok
DESCRIPTION
The character class \d
(also the POSIX character class [:digit:]
) in a regular expression matches all unicode digit character, which might not be what you expect if you are testing if a string can be used as a number in Perl. Instead use either [0-9]
, or if you are on Perl 5.14 or better you can use the /a
modifier. This policy allows \d
in expressions with an explicit /u
modifier (normally on by default), as it indicates that the code is expecting Unicode semantics, including Unicode digits.
/\d/; # not ok
/[[:digit:]]/; # not ok
/\d/a; # ok
/\d/u; # ok
/[[:digit:]]/a; # ok
/[[:digit:]]/u; # ok
/[0-9]/; # ok
AFFILIATION
None.
CONFIGURATION
This policy is not configurable except for the standard options.
CAVEATS
This is not a general policy, and should not be applied toward all applications without some thought. This is frequently true for Perl::Critic policies, but especially so for this policy.
In the general the ability to match against unicode digits is a useful ability, and doesn't constitute bad code. On the other hand, some applications don't ever need to match non-ASCII digit characters, and incorrectly rely on \d
to validate as a number as Perl understands it (and Perl understands non-ASCII digits as zero regardless of what they mean in their respective languages).
This policy doesn't take into account using the re pragma.
use re '/a';
/\d/; # (still) not ok
AUTHOR
Author: Graham Ollis <plicease@cpan.org>
Contributors:
Ville Skyttä (SCOP)
Yoshikazu Sawa (yoshikazusawa)
COPYRIGHT AND LICENSE
This software is copyright (c) 2019-2024 by Graham Ollis.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.