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::Critic::Policy::ValuUserdContributed:PerluDocumentationLeftSideOfEquality(3)y(3)

NAME
       Perl::Critic::Policy::ValuesAndExpressions::RequireConstantOnLeftSideOfEquality
       - Putting the constant value on the left	side of	an equality exposes
       typos.

AFFILIATION
       This policy is part of Perl::Critic::More, a bleeding edge supplement
       to Perl::Critic.

DESCRIPTION
       This policy warns you if	you put	a constant value (i.e. a literal
       number or some string) on the right side	of a "==" operator when	there
       is a variable or	some other lvalue on the left side.  In	a nutshell:

	 if($foo == 42){}    # not ok
	 if(42 == $foo){}    # ok

	 if($foo eq 'bar'){} # not ok
	 if('bar' eq $foo){} # ok

       The rationale is	that sometimes you might mistype "=" instead of	"==",
       and if you're in	the habit of putting the constant value	on the left
       side of the equality, then Perl will give you a compile-time warning.
       Perhaps this is best explained with an example:

	 if ($foo == 42){}  # This is what I want it to	do.
	 if ($foo = 42){}   # But suppose this is what I actually type.
	 if (42	= $foo){}   # If I had (mis)typed it like this,	then Perl gives	a warning.
	 if (42	== $foo){}  # So this is what I	should have attempted to type.

       So this Policy doesn't actually tell you	if you've mistyped "=" instead
       of "==".	 Rather, it encourages you to write your expressions in	a
       certain way so that Perl	can warn you when you mistyped it.

       The "eq"	operator is not	prone to the same type of typo as the "=="
       operator, but this Policy still treats it the same way.	Therefore, the
       rule is consistently applied to all equality operators, which helps you
       to get into the habit of	writing	compliant expressions faster.

CONFIGURATION
       This Policy is not configurable except for the standard options.

AUTHOR
       Jeffrey Ryan Thalhammer <thaljef@cpan.org>

COPYRIGHT
       Copyright (c) 2005-2008 Jeffrey Ryan Thalhammer.	 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.

::Critic::Policy::ValuesAndExpressions::RequireConstantOnLeftSideOfEquality(3)

NAME | AFFILIATION | DESCRIPTION | CONFIGURATION | AUTHOR | COPYRIGHT

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