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Perl::Critic::Policy::User:ContributedlPerl:Documentatio:RequireFinalReturn(3)

NAME
       Perl::Critic::Policy::Subroutines::RequireFinalReturn - End every path
       through a subroutine with an explicit "return" statement.

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

DESCRIPTION
       Require all subroutines to terminate explicitly with one	of the
       following: "return", "carp", "croak", "die", "exec", "exit", "goto", or
       "throw".

       Subroutines without explicit return statements at their ends can	be
       confusing.  It can be challenging to deduce what	the return value will
       be.

       Furthermore, if the programmer did not mean for there to	be a
       significant return value, and omits a return statement, some of the
       subroutine's inner data can leak	to the outside.	 Consider this case:

	   package Password;
	   # every time	the user guesses the password wrong, its value
	   # is	rotated	by one character
	   my $password;
	   sub set_password {
	       $password = shift;
	   }
	   sub check_password {
	       my $guess = shift;
	       if ($guess eq $password)	{
		   unlock_secrets();
	       } else {
		   $password = (substr $password, 1).(substr $password,	0, 1);
	       }
	   }
	   1;

       In this case, the last statement	in check_password() is the assignment.
       The result of that assignment is	the implicit return value, so a	wrong
       guess returns the right password!  Adding a "return;" at	the end	of
       that subroutine solves the problem.

       The only	exception allowed is an	empty subroutine.

       Be careful when fixing problems identified by this Policy; don't
       blindly put a "return;" statement at the	end of every subroutine.

CONFIGURATION
       If you've created your own terminal functions that behave like "die" or
       "exit", then you	can configure Perl::Critic to recognize	those
       functions as well.  Just	put something like this	in your	.perlcriticrc:

	   [Subroutines::RequireFinalReturn]
	   terminal_funcs = quit abort bailout

BUGS
       We do not look for returns inside ternary operators.  That construction
       is too complicated to analyze right now.	 Besides, a better form	is the
       return outside of the ternary like this:	"return	foo ? 1	: bar ?	2 : 3"

AUTHOR
       Chris Dolan <cdolan@cpan.org>

COPYRIGHT
       Copyright (c) 2005-2011 Chris Dolan.

       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.

perl v5.24.1	      Perl::Critic::Policy::Subroutines::RequireFinalReturn(3)

NAME | AFFILIATION | DESCRIPTION | CONFIGURATION | BUGS | AUTHOR | COPYRIGHT

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