NAME

       Perl::Critic::Policy::ValuesAndExpressions::ProhibitLongChainsOfMethodCalls - Long chains
       of method calls indicate tightly coupled code.

AFFILIATION

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

DESCRIPTION

       A long chain of method calls usually indicates that the code knows too much about the
       interrelationships between objects.  If the code is able to directly navigate far down a
       network of objects, then when the network changes structure in the future, the code will
       need to be modified to deal with the change.  The code is too tightly coupled and is
       brittle.

           $x = $y->a;           #ok
           $x = $y->a->b;        #ok
           $x = $y->a->b->c;     #questionable, but allowed by default
           $x = $y->a->b->c->d;  #not ok

CONFIGURATION

       This policy has one option: "max_chain_length" which controls how far the code is allowed
       to navigate.  The default value is 3.

TO DO

       Add a "class_method_exemptions" option to allow for things like

           File::Find::Rule
               ->name('*.blah')
               ->not_name('thingy')
               ->readable()
               ->directory()
               ->in(@roots);

AUTHOR

       Elliot Shank "<perl@galumph.com>"

COPYRIGHT

       Copyright (c) 2007-2011 Elliot Shank.

       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 v5.20.2     Perl::Critic::Policy::ValuesAndExpressions::ProhibitLongChainsOfMethodCalls(3pm)