Perl::Critic::Policy::CodeLayout::ProhibitParensWithBuiltins - Write open $handle, $path instead of open($handle, $path).


This Policy is part of the core Perl::Critic distribution.


Conway suggests that all built-in functions be called without parentheses around the argument list. This reduces visual clutter and disambiguates built-in functions from user functions. Exceptions are made for my, local, and our which require parentheses when called with multiple arguments.

    open($handle, '>', $filename); #not ok
    open $handle, '>', $filename;  #ok

    split(/$pattern/, @list); #not ok
    split /$pattern/, @list;  #ok


This Policy is not configurable except for the standard options.


Coding with parentheses can sometimes lead to verbose and awkward constructs, so I think the intent of Conway's guideline is to remove only the unnecessary parentheses. This policy makes exceptions for some common situations where parentheses are usually required. However, you may find other situations where the parentheses are necessary to enforce precedence, but they cause still violations. In those cases, consider using the '## no critic' comments to silence Perl::Critic.


Some builtin functions (particularly those that take a variable number of scalar arguments) should probably get parentheses. This policy should be enhanced to allow the user to specify a list of builtins that are exempt from the policy.


Jeffrey Ryan Thalhammer <>


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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.