Perl::Critic::Policy::InputOutput::RequireBracedFileHandleWithPrint3pm

Write "print {$fh} $foo, $bar;" instead of "print $fh $foo, $bar;".

Affiliation

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

Overview

The "print" and "printf" functions have a unique syntax that supports an optional file handle argument. Conway suggests wrapping this argument in braces to make it visually stand out from the other arguments. When you put braces around any of the special package-level file handles like "STDOUT", "STDERR", and "DATA", you must add the '*' sigil or else it won't compile under use strict 'subs'.

  print $FH   "Mary had a little lamb\n";  #not ok
  print {$FH} "Mary had a little lamb\n";  #ok
  print   STDERR   $foo, $bar, $baz;  #not ok
  print  {STDERR}  $foo, $bar, $baz;  #won't compile under 'strict'
  print {*STDERR}  $foo, $bar, $baz;  #perfect!

Configuration

This Policy is not configurable except for the standard options.

Releases

10 releases since Debian 5.0 (Lenny); the text changed 9 times.

5.0
6.0
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Arch