Hash::MoreUtils - Provide the stuff missing in Hash::Util
use Hash::MoreUtils qw(:all); my %h = (foo => "bar", FOO => "BAR", true => 1, false => 0); my %s = slice \%h, qw(true false); # (true => 1, false => 0) my %f = slice_false \%h; # (false => 0) my %u = slice_grep { $_ =~ m/^[A-Z]/ }, \%h; # (FOO => "BAR") my %r = safe_reverse \%h; # (bar => "foo", BAR => "FOO", 0 => "false", 1 => "true")
Similar to List::MoreUtils, Hash::MoreUtils contains trivial but commonly-used functionality for hashes. The primary focus for the moment is providing a common API - speeding up by XS is far away at the moment.
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_without
As slice but without any (key/value) pair whose key is in LIST.
If no LIST is given, in opposite to slice an empty list is assumed, thus nothing will be deleted.
slice_missing
Returns a HASH containing the (key => undef) pair for every LIST element (as key) that does not exist hashref.
If no LIST is given there are obviously no non-existent keys in HASHREF so the returned HASH is empty.
HASHREF
slice_notdef
Searches for undefined slices with the given LIST elements as keys in the given HASHREF. Returns a HASHREF containing the slices (key -> undef) for every undefined item.
To search for undefined slices slice_notdef needs a LIST with items to search for (as keys). If no LIST is given it returns an empty HASHREF even when the given HASHREF contains undefined slices.
slice_true
A special slice_grep which returns only those elements of the hash which's values evaluates to TRUE.
slice_grep
TRUE
slice_false
A special slice_grep which returns only those elements of the hash which's values evaluates to FALSE.
FALSE
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 themselves.
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_missing_map
As slice_missing but checks for missing keys (of MAP) and map to the value (of MAP) as key in the returned HASH. The slices of the returned HASHREF are always undefined.
If no MAP is given, slice_missing will be used on HASHREF which will return an empty HASH.
slice_notdef_map
As slice_notdef but checks for undefined keys (of MAP) and map to the value (of MAP) as key in the returned HASH.
If no MAP is given, slice_notdef will be used on HASHREF which will return an empty HASH.
slice_true_map
As slice_map, but only includes pairs whose values are TRUE.
slice_false_map
As slice_map, but only includes pairs whose values are FALSE.
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}"; $v; }; my %easy_rev = safe_reverse \&croak_dup, \%hash
Returns safely reversed hash (value, key pairs of original hash). If no BLOCK is given, following routine will be used:
BLOCK
sub merge_dup { my ($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 2010-2018 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.