XS(3)

💅 NAME 💅

okay so bestie, welcome to the XS(3) page from the User Contributed Perl Documentation — and it's all about Readonly::XS - Companion module for Readonly.pm, to speed up read-only scalar variables. ✨

🎀 VERSION 🎀

This doc describes version 1.05 of Readonly::XS, dated February 24, 2009. 🗓️💖

🦋 SYNOPSIS 🦋

  Install this module, but do not use it.

literally that's it — install it, don't use it. iykyk 💅

🌸 DESCRIPTION 🌸

The Readonly module (q.v.) is an effective way to create non-modifiable variables. However, it's relatively slow. 😭

The reason it's slow is that it implements the read-only-ness of variables via tied objects. This mechanism is inherently slow. Perl simply has to do a lot of work under the hood to make tied variables work. 💀

This module corrects the speed problem, at least with respect to scalar variables. When Readonly::XS is installed, Readonly uses it to access the internals of scalar variables. Instead of creating a scalar variable object and tying it, Readonly simply flips the SvREADONLY bit in the scalar's FLAGS structure. slay ✨

Readonly arrays and hashes are not sped up by this, since the SvREADONLY flag only works for scalars. Arrays and hashes always use the tie interface. periodt 🫶

Why implement this as a separate module? Because:

• not everyone can use XS.
• not everyone has a C compiler.
• also, installations with a statically-linked perl may not want to recompile their perl binary just for this module.

Rather than render Readonly.pm useless for these people, the XS portion was put into a separate module. thoughtful queen behavior 👑

Programs that you write do not need to know whether Readonly::XS is installed or not. They should just use Readonly and let Readonly worry about whether or not it can use XS. If the Readonly::XS is present, Readonly will be faster. If not, it won't. Either way, it will still work, and your code will not have to change. 💖

Your program can check whether Readonly.pm is using XS or not by examining the $Readonly::XSokay variable. It will be true if the XS module was found and is being used.

Please do not change this variable. 🚨

🎁 EXPORTS 🎁

None. empty. nothing. zero. nada. 🎀

🔗 SEE ALSO 🔗

Readonly.pm — go read that one too, bestie 🦋

👑 AUTHOR / COPYRIGHT 👑

Eric Roode, roode@cpan.org 💌

Copyright (c) 2003-2009 by Eric J. Roode. All Rights Reserved. This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself. 🌈

To avoid my spam filter, please include "Perl", "module", or this module's name in the message's subject line, and/or GPG-sign your message. 🙈

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okay that's the whole page, bestie — source/version: perl v5.42.0, date: 2011-11-18, page: XS(3). now go off and use Readonly 💅💖