NAME

Syntax::Operator::Matches - match::simple but as a real infix operator

SYNOPSIS

On Perl v5.38 or later:

   use v5.38;
   use Syntax::Operator::Matches;

   if ( $x matches $y ) {
      ...;
   }

DESCRIPTION

This module implements a matches infix operator using match::simple.

There's also a mismatches operator which returns the inverse. This needs to be requested explicitly.

   use v5.38;
   use Syntax::Operator::Matches qw( matches mismatches );
   
   unless ( $x mismatches $y ) {
      ...;
   }

What matches what?

As a reminder of what match::simple's matching rules are:

• 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.

Use with Type::Tiny

Type::Tiny type constraints overload the ~~ operator, so the following will work:

  use Types::Standard qw( Str ArrayRef );
  use Syntax::Operator::Matches;
  
  if ( $x matches Str ) {
    say $x;
  }
  elsif ( $x matches ArrayRef[Str] ) {
    say $_ for $x->@*;
  }
  else {
    warn "Unexpected input";
  }

SEE ALSO

match::simple.

AUTHOR

Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE

This software is copyright (c) 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.