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match::simple(3pm) User Contributed Perl Documentation match::simple(3pm)

NAME

match::simple - simplified clone of smartmatch operator

SYNOPSIS

   use v5.10;
   use match::simple;
   
   if ( $this |M| $that ) {
      say "$this matches $that";
   }

DESCRIPTION

match::simple provides a simple match operator "|M|" that acts like a sane subset of the (as of Perl 5.18) deprecated smart match operator. Unlike smart match, the behaviour of the match is determined entirely by the operand on the right hand side.

  • If the right hand side is "undef", then there is only a match if the left hand side is also "undef".
  • If the right hand side is a non-reference, then the match is a simple string match.
  • If the right hand side is a reference to a regexp, then the left hand is evaluated .
  • If the right hand side is a code reference, then it is called in a boolean context with the left hand side being passed as an argument.
  • If the right hand side is an object which provides a "MATCH" method, then it this is called as a method, with the left hand side being passed as an argument.
  • If the right hand side is an object which overloads "~~", then this will be used.
  • If the right hand side is an arrayref, then the operator recurses into the array, with the match succeeding if the left hand side matches any array element.
  • If any other value appears on the right hand side, the operator will croak.

If you don't like the crazy Sub::Infix operator, you can alternatively export a more normal function:

   use v5.10;
   use match::simple qw(match);
   
   if ( match($this, $that) ) {
      say "$this matches $that";
   }

If you're making heavy use of this module, then this is probably your best option, as it runs significantly faster.

XS Backend

If you install match::simple::XS, a faster XS-based implementation will be used instead of the pure Perl functions. Depending on what sort of match you are doing, this is likely to be several times faster. In extreme cases, such as matching a string in an arrayref, it can be twenty-five times faster, or more. However, where $that is a single regexp, it's around 30% slower. Overall though, I think the performance improvement is worthwhile.

If you want to take advantage of this speed up, use the "match" function rather than the "|M|" operator. Otherwise all your gains will be lost to the slow implementation of operator overloading.

The constant "match::simple::IMPLEMENTATION" tells you which backend is currently in use.

Environment

Setting the "MATCH_SIMPLE_IMPLEMENTATION" environment variable to "PP" encourages match::simple to use the pure Perl backend.

BUGS

Please report any bugs to <https://github.com/tobyink/p5-match-simple/issues>.

SEE ALSO

match::smart, match::simple::sugar.

This module uses Exporter::Tiny.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 2013-2014, 2017, 2022-2023 by Toby Inkster.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

DISCLAIMER OF WARRANTIES

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

2024-07-24 perl v5.38.2