perl::critic::policy::subroutines::requirefinalreturn(3) [centos man page]

Perl::Critic::Policy::Subroutines::RequireFinalReturn(3)User Contributed Perl DocumentatioPerl::Critic::Policy::Subroutines::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 v5.16.3							    2014-06-09		  Perl::Critic::Policy::Subroutines::RequireFinalReturn(3)

Check Out this Related Man Page

Perl::Critic::Policy::ControlStructures::ProhibitUnreachUserCContributed Perl DPerl::Critic::Policy::ControlStructures::ProhibitUnreachableCode(3)

NAME

       Perl::Critic::Policy::ControlStructures::ProhibitUnreachableCode - Don't write code after an unconditional "die, exit, or next".

AFFILIATION

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

DESCRIPTION

       This policy prohibits code following a statement which unconditionally alters the program flow.	This includes calls to "exit", "die",
       "return", "next", "last" and "goto".  Due to common usage, "croak" and "confess" from Carp are also included.

       Code is reachable if any of the following conditions are true:

       o   Flow-altering statement has a conditional attached to it

       o   Statement is on the right side of an operator "&&", "||", "//", "and", "or", or "err".

       o   Code is prefixed with a label (can potentially be reached via "goto")

       o   Code is a subroutine

EXAMPLES

	 # not ok

	 exit;
	 print "123
";

	 # ok

	 exit if !$xyz;
	 print "123
";

	 # not ok

	 for ( 1 .. 10 ) {
	     next;
	     print 1;
	 }

	 # ok

	 for ( 1 .. 10 ) {
	     next if $_ == 5;
	     print 1;
	 }

	 # not ok

	 sub foo {
	     my $bar = shift;
	     return;
	     print 1;
	 }

	 # ok

	 sub foo {
	     my $bar = shift;
	     return if $bar->baz();
	     print 1;
	 }

	 # not ok

	 die;
	 print "123
";

	 # ok

	 die;
	 LABEL: print "123
";

	 # not ok

	 croak;
	 do_something();

	 # ok

	 croak;
	 sub do_something {}

CONFIGURATION

       This Policy is not configurable except for the standard options.

SEE ALSO

       Perl::Critic::Policy::ControlStructures::ProhibitPostfixControls

AUTHOR

       Peter Guzis <pguzis@cpan.org>

COPYRIGHT

       Copyright (c) 2006-2011 Peter Guzis.  All rights reserved.

       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 v5.16.3							    2014-06-09 Perl::Critic::Policy::ControlStructures::ProhibitUnreachableCode(3)

Linux and UNIX Man Pages

perl::critic::policy::subroutines::requirefinalreturn(3) [centos man page]

Check Out this Related Man Page