file::find::wanted(3pm) [debian man page]

Wanted(3pm)						User Contributed Perl Documentation					       Wanted(3pm)

NAME

       File::Find::Wanted - More obvious wrapper around File::Find

VERSION

       Version 1.00

SYNOPSIS

       File::Find is a great module, except that it doesn't actually find anything.  Its "find()" function walks a directory tree and calls a
       callback function.  Unfortunately, the callback function is deceptively called "wanted", which implies that it should return a boolean
       saying whether you want the file.  That's not how it works.

       Most of the time you call "find()", you just want to build a list of files.  There are other modules that do this for you, most notably
       Richard Clamp's great File::Find::Rule, but in many cases, it's overkill, and you need to learn a new syntax.

       With the "find_wanted" function, you supply a callback sub and a list of starting directories, but the sub actually should return a boolean
       saying whether you want the file in your list or not.

       To get a list of all files ending in .jpg:

	   my @files = find_wanted( sub { -f && /.jpg$/ }, $dir );

       For a list of all directories that are not CVS or .svn:

	   my @files = find_wanted( sub { -d && !/^(CVS|.svn)$/ }, $dir ) );

       It's easy, direct, and simple.

WHY DO THIS
?
       The cynical may say "that's just the same as doing this":

	   my @files;
	   find( sub { push @files, $File::Find::name if -f && /.jpg$/ }, $dir );

       Sure it is, but File::Find::Wanted makes it more obvious, and saves a line of code.  That's worth it to me.  I'd like it if find_wanted()
       made its way into the File::Find distro, but for now, this will do.

FUNCTIONS

   find_wanted( &wanted, @directories )
       Descends through @directories, calling the wanted function as it finds each file.  The function returns a list of all the files and
       directories for which the wanted function returned a true value.

       This is just a wrapper around "File::Find::find()".  See File::Find for details on how to modify its behavior.

COPYRIGHT &; LICENSE
       Copyright 2005-2012 Andy Lester.

       This program is free software; you can redistribute it and/or modify it under the terms of the Artistic License v2.0.

perl v5.14.2							    2012-06-08							       Wanted(3pm)

File::Find::Rule::Extending(3)				User Contributed Perl Documentation			    File::Find::Rule::Extending(3)

NAME

       File::Find::Rule::Extending - the mini-guide to extending File::Find::Rule

SYNOPSIS

	package File::Find::Rule::Random;
	use strict;

	# take useful things from File::Find::Rule
	use base 'File::Find::Rule';

	# and force our crack into the main namespace
	sub File::Find::Rule::random () {
	    my $self = shift()->_force_object;
	    $self->exec( sub { rand > 0.5 } );
	}

	1;

DESCRIPTION

       File::Find::Rule went down so well with the buying public that everyone wanted to add extra features.  With the 0.07 release this became a
       possibility, using the following conventions.

   Declare your package
	package File::Find::Rule::Random;
	use strict;

   Inherit methods from File::Find::Rule
	# take useful things from File::Find::Rule
	use base 'File::Find::Rule';

       Force your madness into the main package

	# and force our crack into the main namespace
	sub File::Find::Rule::random () {
	    my $self = shift()->_force_object;
	    $self->exec( sub { rand > 0.5 } );
	}

       Yes, we're being very cavalier here and defining things into the main File::Find::Rule namespace.  This is due to lack of imaginiation on
       my part - I simply can't find a way for the functional and oo interface to work without doing this or some kind of inheritance, and
       inheritance stops you using two File::Find::Rule::Foo modules together.

       For this reason try and pick distinct names for your extensions.  If this becomes a problem then I may institute a semi-official registry
       of taken names.

   Taking no arguments.
       Note the null prototype on random.  This is a cheat for the procedural interface to know that your sub takes no arguments, and so allows
       this to happen:

	find( random => in => '.' );

       If you hadn't declared "random" with a null prototype it would have consumed "in" as a parameter to it, then got all confused as it doesn't
       know about a '.' rule.

AUTHOR

       Richard Clamp <richardc@unixbeard.net>

COPYRIGHT

       Copyright (C) 2002 Richard Clamp.  All Rights Reserved.

       This module is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

SEE ALSO

       File::Find::Rule

       File::Find::Rule::MMagic was the first extension module, so maybe check that out.

perl v5.18.2							    2011-09-19					    File::Find::Rule::Extending(3)