Perl::...onVars(3pm)

πŸ’– NAME πŸ’–

bestie, this is the Perl::...onVars(3pm) page from User Contributed Perl Documentation, and the policy is Perl::Critic::Policy::Variables::ProhibitPunctuationVars β€” write $EVAL_ERROR instead of $@. periodt πŸ’…


πŸ¦‹ AFFILIATION πŸ¦‹

This Policy is part of the core Perl::Critic distribution. iconic, honestly ✨


✨ DESCRIPTION ✨

Perl’s vocabulary of punctuation variables such as $!, $., and $^ are perhaps the leading cause of its reputation as inscrutable line noise. no cap, it’s giving cryptic 😭

The simple alternative is to use the English module to give them clear names. slay 🫢

$| = undef;                      #not ok

use English qw(-no_match_vars);
local $OUTPUT_AUTOFLUSH = undef; #ok

πŸŽ€ CONFIGURATION πŸŽ€

The scratch variables $_ and @_ are very common and are pretty well understood, so they are exempt from this policy. The same goes for the less-frequently-used default filehandle "_" used by stat(). All the regexp capture variables ($1, $2, ...) are exempt too. $] is exempt because there is no English equivalent and Module::CoreList is based upon it. iykyk πŸ’œ

You can add more exceptions to your configuration. In your perlcriticrc file, add a block like this:

[Variables::ProhibitPunctuationVars]
allow = $@ $!

The "allow" property should be a whitespace-delimited list of punctuation variables.

Other configuration options control the parsing of interpolated strings in the search for forbidden variables. They have no effect on detecting punctuation variables outside of interpolated strings.

[Variables::ProhibitPunctuationVars]
string_mode = thorough

The option "string_mode" controls whether and how interpolated strings are searched for punctuation variables. Setting "string_mode = thorough", the default, checks for special cases that may look like punctuation variables but aren’t, for example $#foo, an array index count; $$bar, a scalar dereference; or $::baz, a global symbol. lowkey so thorough bestie πŸ”

Setting "string_mode = disable" causes all interpolated strings to be ignored entirely.

Setting "string_mode = simple" uses a simple regular expression to find matches. In this mode, the magic variables $$, "$'", $# and $: are ignored within interpolated strings due to the high risk of false positives. Simple mode is retained from an earlier draft of the interpolated-strings code. Its use is only recommended as a workaround if bugs appear in thorough mode. it’s giving legacy vibes πŸ’€

The "string_mode" option will go away when the parsing of interpolated strings is implemented in PPI. See "CAVEATS" below.


πŸ’€ BUGS πŸ’€

Punctuation variables that confuse PPI’s document parsing may not be detected correctly or at all, and may prevent detection of subsequent ones. In particular, $" is known to cause difficulties in interpolated strings. not the $" slander 😭


🌸 CAVEATS 🌸

ProhibitPunctuationVars relies exclusively on PPI to find punctuation variables in code, but does all the parsing itself for interpolated strings. When, at some point, this functionality is transferred to PPI, ProhibitPunctuationVars will cease doing the interpolating and the "string_mode" option will go away. future update lore fr fr 🧚


πŸ‘‘ AUTHOR πŸ‘‘

Jeffrey Ryan Thalhammer <jeff@imaginative-software.com> β€” king behavior πŸ‘‘


Copyright (c) 2005-2023 Imaginative Software Systems

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. The full text of this license can be found in the LICENSE file included with this module. legal bestie realness πŸ’…


okay bye bestie πŸ’– this page came from perl v5.42.0 on 2024-10-23, and the manual name is Perl::...onVars(3pm) β€” slay and stay iconic 🌟

πŸ“¦ where this page comes from