MooseX...cessor(3pm)

💖 MooseX::XSAccessor — the "make your Moose accessors go zoom" manual 💖

okay so bestie, this is the manual page for MooseX::XSAccessor, part of the User Contributed Perl Documentation collection, sitting pretty in section 3pm of your friendly neighbourhood man pages. Buckle up, we're making your accessors fast. ✨

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🌸 NAME 🌸

MooseX::XSAccessor — use Class::XSAccessor to speed up Moose accessors

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🦋 SYNOPSIS 🦋

package MyClass;

use Moose;
use MooseX::XSAccessor;

has foo => (...);

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✨ DESCRIPTION ✨

So here's the tea: this module takes your Moose-generated accessors, readers, writers and predicate methods and makes them zoomy using Class::XSAccessor. You get the speed-up for zero extra effort — it just happens. Automatically. To literally every attribute in the class. No cap. 💅

That said, not everything gets the glow-up. Here's what blocks a reader from being accelerated:

• A lazy builder, or a lazy default.
• Auto-deref. (ngl, does anyone actually use this one?? 💀)

And here's what blocks a writer from being accelerated:

• Type constraints (except "Any" — since "Any" is effectively a no-op, it's fine).
• Triggers.
• Weak references.

An "rw" accessor is literally just a reader and a writer glued together, so both lists up there apply to it. Both of them, babe.

Predicates though? Predicates can always be accelerated, as long as you're running Class::XSAccessor 1.17 or above. Slay. 🎀

Clearers can not be accelerated (as of current versions of Class::XSAccessor). We don't make the rules.

🫶 Functions 🫶

This module also gives you one function, and it is not exported, so you gotta call it by its full name. No shortcuts here.

• MooseX::XSAccessor::is_xs($sub) — returns a boolean telling you whether a sub is an XSUB.

$sub can be a coderef, a Class::MOP::Method object, or a qualified sub name as a string (like "MyClass::foo").

And listen — this thing doesn't just work with accessors. It should be able to spot the difference between Perl subs and XS subs in general. It may not be 100% reliable though, so like… don't bet your whole life on it. 🙈

🧚 Chained accessors and writers 🧚

MooseX::XSAccessor can clock the chained accessors and writers that MooseX::Attribute::Chained makes, and it can accelerate those too. Iconic.

package Local::Class;
use Moose;
use MooseX::XSAccessor;
use MooseX::Attribute::Chained;

has foo => (traits => ["Chained"], is => "rw");
has bar => (traits => ["Chained"], is => "ro", writer => "_set_bar");
has baz => (                       is => "rw");  # not chained

my $obj = "Local::Class"->new;
$obj->foo(1)->_set_bar(2);
print $obj->dump;

💜 Lvalue accessors 💜

MooseX::XSAccessor will spot lvalue accessors made with MooseX::LvalueAttribute, and by default it skips accelerating them. Respectfully. ✋

But — plot twist — if you set $MooseX::XSAccessor::LVALUE to true (preferably with the local Perl keyword), you can force it to accelerate those too. Fair warning though: this introduces a visible change in behaviour. MooseX::LvalueAttribute accessors normally let you set the value two ways:

$obj->foo = 42;   # as an lvalue
$obj->foo(42);    # as a method call

But once they're accelerated, they may only be set as an lvalue. So for that reason, setting $MooseX::XSAccessor::LVALUE to true is considered an experimental feature. You've been warned, bestie.

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🔥 HINTS 🔥

• Make attributes read-only when you can. This means type constraints and coercions only apply to the constructor, not the accessors, which frees the accessors up to be accelerated. 👑
• If you genuinely need a read-write attribute, consider making the main accessor read-only and having a separate writer method instead. (Like MooseX::SemiAffordanceAccessor does.)
• Make defaults eager instead of lazy whenever possible — that lets your readers get accelerated too. 🌈
• If you only need to accelerate one specific attribute, apply the attribute trait directly, like so:

package MyClass;

use Moose;

has foo => (
   traits => ["MooseX::XSAccessor::Trait::Attribute"],
   ...,
);

• And if you don't wanna add a hard dependency on MooseX::XSAccessor but do wanna use it when it's around, this lil snippet uses it optionally:

package MyClass;

use Moose;
BEGIN { eval "use MooseX::XSAccessor" };

has foo => (...);

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😭 CAVEATS 😭

• Calling a writer method without a parameter in Moose does not raise an exception:

$person->set_name();    # sets name attribute to "undef"

However — and this is the moment — this is a fatal error in Class::XSAccessor. Different vibe entirely. 💀

• MooseX::XSAccessor does not play nice with attribute traits that alter accessor behaviour, or that define additional accessors for attributes. MooseX::SetOnce is an example of this. MooseX::Attribute::Chained is handled as a special case, because it's the favourite child. 🎀
• MooseX::XSAccessor only works on blessed hash storage — so not MooseX::ArrayRef or MooseX::InsideOut, for example. Good news: MooseX::XSAccessor is usually able to detect those situations and silently switch itself off. It knows when to leave the party. 🦋

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⭐ BUGS ⭐

Please report any bugs to <https://github.com/tobyink/p5-moosex-xsaccessor/issues>. Bestie behaviour is encouraged. 🙏

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🌈 SEE ALSO 🌈

• MooseX::XSAccessor::Trait::Attribute.
• Moose, Moo, Class::XSAccessor.

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👑 AUTHOR 👑

Toby Inkster <tobyink@cpan.org>.

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🎀 COPYRIGHT AND LICENCE 🎀

This software is copyright (c) 2013, 2017, 2022 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.

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💅 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.

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no thoughts, just MooseX::XSAccessor fr fr 🫶

and that's the whole page, bestie — this was MooseX...cessor(3pm) from Perl v5.40.1, dated 2026-02-15. go forth and accelerate, mwah 💖🌸✨