--- name: "Syntax::Keyword::Junction" section: "3pm" platform: "linux" package: "libsyntax-keyword-junction-perl" version: "0.003009-1" release: "Debian 13 (Trixie)" platforms: ["linux"] url: "https://new.carta.tech/Syntax::Keyword::Junction" --- # Syntax::Keyword::Junction(3pm) Comparisons against multiple values ## NAME Syntax::Keyword::Junction - Comparisons against multiple values ## SYNOPSIS ``` use Syntax::Keyword::Junction qw/ all any none one /; if (any(@grant) eq 'su') { ... } if (all($foo, $bar) >= 10) { ... } if (qr/^\d+$/ == all(@answers)) { ... } if (all(@input) <= scalar @limits) { ... } if (none(@pass) eq 'password') { ... } if (one(@answer) == 42) { ... } ``` or if you want to rename an export, use Sub::Exporter options: ``` use Syntax::Keyword::Junction any => { -as => 'robot_any' }; if (robot_any(@grant) eq 'su') { ... } ``` ## DESCRIPTION This is a lightweight module which provides 'Junction' operators, the most commonly used being `"any"` and `"all"`. Inspired by the Perl 6 design docs, \. Provides a limited subset of the functionality of Quantum::Superpositions, see "SEE ALSO" for comment. Notice in the "SYNOPSIS" above, that if you want to match against a regular expression, you must use `"=="` or `"!="`. **Not** `"=~"` or `"!~"`. You must also use a regex object, such as `"qr/\d/"`, not a plain regex such as `"/\d/"`. ## SUBROUTINES ### all() Returns an object which overloads the following operators: ``` '<', '<=', '>', '>=', '==', '!=', 'lt', 'le', 'gt', 'ge', 'eq', 'ne', '~~' ``` Returns true only if **all** arguments test true according to the operator used. ### any() Returns an object which overloads the following operators: ``` '<', '<=', '>', '>=', '==', '!=', 'lt', 'le', 'gt', 'ge', 'eq', 'ne', '~~' ``` Returns true if **any** argument tests true according to the operator used. ### none() Returns an object which overloads the following operators: ``` '<', '<=', '>', '>=', '==', '!=', 'lt', 'le', 'gt', 'ge', 'eq', 'ne', '~~' ``` Returns true only if **no** argument tests true according to the operator used. ### one() Returns an object which overloads the following operators: ``` '<', '<=', '>', '>=', '==', '!=', 'lt', 'le', 'gt', 'ge', 'eq', 'ne', '~~' ``` Returns true only if **one and only one** argument tests true according to the operator used. ## ALTERING JUNCTIONS You cannot alter junctions. Instead, you can create new junctions out of old junctions. You can do this by calling the `"values"` method on a junction. ``` my $numbers = any(qw/1 2 3 4 5/); print $numbers == 3 ? 'Yes' : 'No'; # Yes $numbers = any( grep { $_ != 3 } $numbers->values ); print $numbers == 3 ? 'Yes' : 'No'; # No ``` You can also use the `"map"` method: ``` my $numbers = any(qw/1 2 3 4 5/); my $prime = $numbers->map( \&is_prime ); say for $prime->values; # prints 0, 1, 1, 0, 1 ``` ## EXPORT 'all', 'any', 'none', 'one', as requested. All subroutines can be called by its fully qualified name, if you don't want to export them. ``` use Syntax::Keyword::Junction; if (Syntax::Keyword::Junction::any( @questions )) { ... } ``` ## WARNING When comparing against a regular expression, you must remember to use a regular expression object: `"qr/\d/"` **Not** `"/d/"`. You must also use either `"=="` or `"!="`. This is because `"=~"` and `"!~"` cannot be overridden. ## TO DO Add overloading for arithmetic operators, such that this works: ``` $result = any(2,3,4) * 2; if ($result == 8) {...} ``` ## SEE ALSO This module is actually a fork of Perl6::Junction with very few (initial) changes. The reason being that we want to avoid the incendiary name containing Perl 6. Quantum::Superpositions provides the same functionality as this, and more. However, this module provides this limited functionality at a much greater runtime speed, with my benchmarks showing between 500% and 6000% improvement. \ - "The Wonderful World of Junctions". ## BUGS Please report any bugs or feature requests on the bugtracker website \ When submitting a bug or request, please include a test-file or a patch to an existing test-file that illustrates the bug or desired feature. ## CONTRIBUTORS - • Arthur Axel 'fREW' Schmidt \ - • Carl Franks \ - • David Steinbrunner \ - • Graham Knop \ - • Maxime Soulé \ - • Michael Schout \ - • Olivier Mengué \ - • Paul Cochrane \ - • Ricardo Signes \ - • Rob Hoelz \ ## AUTHORS - • Arthur Axel "fREW" Schmidt \ - • Carl Franks ## COPYRIGHT AND LICENSE This software is copyright (c) 2024 by Arthur Axel "fREW" Schmidt. This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.