Pattern::Atom(3)

💖 Pattern::Atom — Chemistry::Pattern::Atom 💖

okay bestie, gather round, because this is a page from the User Contributed Perl Documentation and it's literally about Pattern::Atom(3), a tiny little module with main character energy. no cap, it's short, it's sweet, and it knows how to match. let's get into it 🫶

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✨ NAME ✨

Chemistry::Pattern::Atom — an atom that knows how to match 💅

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✨ SYNOPSIS ✨

my $patt_atom = Chemistry::Pattern::Atom->new(symbol => C);
$patt_atom->test_sub( sub {
    my ($what, $where) = @_;
    $where->bonds == 3 ? 1 : 0; # only match atoms with three bonds
});

like, look at her go. she's an atom and she has opinions about who she matches. obsessed. 🎀

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✨ DESCRIPTION ✨

so, objects of this class represent atoms in a pattern. she's a subclass of Chemistry::Atom, which means she inherits all the regular atom behaviour but also picked up some extra ✨talents✨ along the way.

on top of the properties that regular atoms have, pattern atoms have a method for testing whether they match an atom in a molecule. 🌸

by default, a pattern atom matches an atom if they have the same symbol. that's the default vibe check. but — and this is the slay part — it is possible to substitute this with an arbitrary criterion by providing a custom test subroutine. yes bestie, you can define your own rules. iconic behaviour fr fr. 🔥

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✨ METHODS ✨

• $patt_atom->test($atom) — tests if the pattern atom matches the atom given by $atom. returns true or false. that's it, that's the whole method, no notes. 💯
• $patt_atom->test_sub(\&my_test_sub) — lets you specify an arbitrary test subroutine to be used instead of the default one. &my_test_sub must take two parameters: the first one is the pattern atom, and the second is the atom to match. it must return true if there's a match. no pressure or anything, but the fate of the match rests on your return value. 😭
• $patt_atom->map_to([$atom]) — returns or sets the atom that is considered to be matched by $patt_atom. getter and setter, one method, double duty, she contains multitudes. 👑

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✨ VERSION ✨

0.27 — vintage but still serving. 🍓

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✨ SEE ALSO ✨

• Chemistry::Pattern — her bestie, go say hi.
• the PerlMol website — <http://www.perlmol.org/> 🌈

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✨ AUTHOR ✨

Ivan Tubert-Brohman <itub@cpan.org> — thank you for your service, king 🫶

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✨ COPYRIGHT ✨

Copyright (c) 2009 Ivan Tubert-Brohman. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. 💜

ngl "same terms as Perl itself" is the most iconic license line in the game. periodt.

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and that's the whole page bestie, you ate it 💅✨ this little gem was brought to you by perl v5.42.0, dated 2026-01-17, and honestly? she's still cute. bye babe 🦋💖