Hash::MoreUtils - Provide the stuff missing in Hash::Util
use Hash::MoreUtils qw(slice slice_def slice_exists slice_grep hashsort );
Similar to List::MoreUtils, Hash::MoreUtils contains trivial but commonly-used functionality for hashes.
List::MoreUtils
Hash::MoreUtils
slice
Returns a hash containing the (key, value) pair for every key in LIST.
If no LIST is given, all keys are assumed as LIST.
LIST
slice_def
As slice, but only includes keys whose values are defined.
slice_exists
As slice but only includes keys which exist in the hashref.
slice_grep
As slice, with an arbitrary condition.
Unlike grep, the condition is not given aliases to elements of anything. Instead, %_ is set to the contents of the hashref, to avoid accidentally auto-vivifying when checking keys or values. Also, 'uninitialized' warnings are turned off in the enclosing scope.
grep
%_
slice_map
Returns a hash containing the (key, value) pair for every key in MAP.
MAP
If no MAP is given, all keys of HASHREF are assumed mapped to theirself.
HASHREF
slice_def_map
As slice_map, but only includes keys whose values are defined.
slice_exists_map
As slice_map but only includes keys which exist in the hashref.
slice_grep_map
As slice_map, with an arbitrary condition.
hashsort
my @array_of_pairs = hashsort \%hash; my @pairs_by_length = hashsort sub { length($a) <=> length($b) }, \%hash;
Returns the (key, value) pairs of the hash, sorted by some property of the keys. By default (if no sort block given), sorts the keys with cmp.
cmp
I'm not convinced this is useful yet. If you can think of some way it could be more so, please let me know.
safe_reverse
my %dup_rev = safe_reverse \%hash sub croak_dup { my ($k, $v, $r) = @_; exists( $r->{$v} ) and croak "Cannot safe reverse: $v would be mapped to both $k and $r->{$v}"; $v; }; my %easy_rev = save_reverse \&croak_dup, \%hash
Returns safely reversed hash (value, key pairs of original hash). If no BLOCK is given, following routine will be used:
BLOCK
sub merge_dup { my ($k, $v, $r) = @_; return exists( $r->{$v} ) ? ( ref($r->{$v}) ? [ @{$r->{$v}}, $k ] : [ $r->{$v}, $k ] ) : $k; };
The BLOCK will be called with 3 arguments:
key
The key from the ( key, value ) pair in the original hash
( key, value )
value
The value from the ( key, value ) pair in the original hash
ref-hash
Reference to the reversed hash (read-only)
The BLOCK is expected to return the value which will used for the resulting hash.
Hans Dieter Pearcey, <hdp@cpan.org>, Jens Rehsack, <rehsack@cpan.org>
<hdp@cpan.org>
<rehsack@cpan.org>
Please report any bugs or feature requests to bug-hash-moreutils@rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Hash-MoreUtils. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.
bug-hash-moreutils@rt.cpan.org
You can find documentation for this module with the perldoc command.
perldoc Hash::MoreUtils
You can also look for information at:
RT: CPAN's request tracker
http://rt.cpan.org/NoAuth/Bugs.html?Dist=Hash-MoreUtils
AnnoCPAN: Annotated CPAN documentation
http://annocpan.org/dist/Hash-MoreUtils
CPAN Ratings
http://cpanratings.perl.org/d/Hash-MoreUtils
Search CPAN
http://search.cpan.org/dist/Hash-MoreUtils/
Copyright 2005 Hans Dieter Pearcey, all rights reserved. Copyright 2010-2013 Jens Rehsack
This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.
See http://dev.perl.org/licenses/ for more information.
To install Hash::MoreUtils, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Hash::MoreUtils
CPAN shell
perl -MCPAN -e shell install Hash::MoreUtils
For more information on module installation, please visit the detailed CPAN module installation guide.