NAME
Perl::Critic::Policy::BuiltinFunctions::ProhibitIndirectBooleanGrep - Use any or first, not a sub that returns a grep, for truth or the first match.
VERSION
version 0.001
DESCRIPTION
BuiltinFunctions::ProhibitBooleanGrep reports a grep whose result is only tested for truth, because any from List::Util stops at the first match and the grep reads the whole list. It cannot see the same grep one call away:
my sub waiting { return grep { !$out{$_} } @found }
...
while ( waiting() ) { ... } # reportedThis policy reports such a call. The result of the sub is a grep: the value of a return, or its last statement. The call is reported where the caller uses only whether the result is empty, and where it uses only the first element, which first finds without reading the rest:
my ($next) = waiting(); # reportedThe report is at the call and not at the sub, because the same sub can be right for a caller that wants the list. The fix is usually a second sub, or any or first at the call.
Where the sub can be
In the same file, by its name. In another file of the same distribution, which Perl::Critic::Distribution reads: a package sub, called by its full name, as Some::hits(), or by its bare name from the same package. A policy that reads the distribution through the same library shares its parse.
Truth
A call is tested for truth when it is, or is an operand of !, not, &&, ||, and or or inside, the condition of if, elsif, unless, while or until, of a postfix modifier, or of a ternary. So is a call under ! or not anywhere, and the left operand of and, or, && or || that starts a statement, such as check() or die.
What it leaves alone
A call in list context, a count, a comparison, or a call through scalar(). A sub that asks wantarray, because it chooses its own result for scalar context. A grep that reaches the return through a variable, and one inside an inner anonymous sub. A method call, because the method that runs can be another sub of the same name. A bare call of a sub from another file in another package, because what it imports is not known. A map, for which there is no any to use instead.
CONFIGURATION
This Policy is not configurable except for the standard options.
METHODS
supported_parameters
default_severity
default_themes
applies_to
The whole document, because a call can come before the sub that it calls.
initialize_if_enabled
Registers what this policy needs from each file of a distribution with Perl::Critic::Distribution: the package subs whose value is a grep. A lexical sub is left out, because no other file can call it.
violates
FUNCTIONS
The steps of violates, for its tests.
grep_subs_in
my @found = grep_subs_in( $ppi, packages_in($ppi) );Each sub of a document whose value is a grep, as a pair of its statement and its full name. A sub that asks wantarray is not one.
returns_grep
Whether the value of a block is a grep: the value of a return anywhere in it, or its last statement. Not a return inside an inner sub, which returns from that sub.
packages_in
The package statements of a document, in order, for package_at. A document is searched once, and not once for each element.
package_at
my $package = package_at( $elem, packages_in($ppi) );The package that an element is in: that of the block of a package NAME { } around it, or else that of the last package NAME; before it, or main.
is_call
Whether a word is a call of a sub by that name, and not a method, a hash key, the left of a fat comma, or the name in a sub statement.
use_of
How the caller uses the result of a call: truth, first, or nothing. "Truth" says when a call is tested for truth.
BUGS
Please report any bugs or feature requests on the bugtracker website https://github.com/teodesian/perl-critic-policy-prohibitindirectbooleangrep/issues
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.
AUTHORS
Current Maintainers:
George S. Baugh <george@troglodyne.net>
COPYRIGHT AND LICENSE
Copyright (c) 2026 Troglodyne LLC
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.