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Full Discussion: nested for loops
Top Forums Shell Programming and Scripting nested for loops Post 302357422 by taiL on Tuesday 29th of September 2009 07:35:05 PM
Old 09-29-2009
nested for loops

I need help getting over this bump on how nested for loops work in shell. Say i was comparing files in a directory in any other language my for loop would look like so

for(int i=0;to then end; i++)
for(int y = i+1; to the end; y++)

I can't seem to understand how i can translate that into shell,
where I want the first for loop to start at the first file and the second for loop to start at the second.

so
Code:
for f in $aDirectory; do
  for f in $aDiredtory

confuses me. Since f in both loops would start at the same file. Any recommendations?
 

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Perl::Critic::Policy::ControlStructures::ProhibitDeepNesUser)Contributed Perl DocumenPerl::Critic::Policy::ControlStructures::ProhibitDeepNests(3)

NAME
Perl::Critic::Policy::ControlStructures::ProhibitDeepNests - Don't write deeply nested loops and conditionals. AFFILIATION
This Policy is part of the core Perl::Critic distribution. DESCRIPTION
Deeply nested code is often hard to understand and may be a sign that it needs to be refactored. There are several good books on how to refactor code. I like Martin Fowler's "Refactoring: Improving The Design of Existing Code". CONFIGURATION
The maximum number of nested control structures can be configured via a value for "max_nests" in a .perlcriticrc file. Each for-loop, if- else, while, and until block is counted as one nest. Postfix forms of these constructs are not counted. The default maximum is 5. Customization in a .perlcriticrc file looks like this: [ControlStructures::ProhibitDeepNests] max_nests = 3 AUTHOR
Jeffrey Ryan Thalhammer <jeff@imaginative-software.com> COPYRIGHT
Copyright (c) 2005-2011 Imaginative Software Systems. 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::ProhibitDeepNests(3)
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