/ 
Data-Difference-0.113001
River stage zero No dependents
/ Data::Difference

NAME

Data::Difference - Compare simple hierarchical data

VERSION

version 0.113001

DESCRIPTION

Data::Difference will compare simple data structures returning a list of details about what was added, removed or changed. It will currently handle SCALARs, HASH references and ARRAY references.

Each change is returned as a hash with the following element.

path

path will be an ARRAY reference containing the hierarchical path to the value, each element in the array will be either the key of a hash or the index on an array

a

If it exists it will contain the value from the first argument passed to data_diff. If it does not exist then this element did not exist in the first argument.

b

If it exists it will contain the value from the second argument passed to data_diff. If it does not exist then this element did not exist in the second argument.

PERL VERSION

This library should run on perls released even a long time ago. It should work on any version of perl released in the last five years.

Although it may work on older versions of perl, no guarantee is made that the minimum required version will not be increased. The version may be increased for any reason, and there is no promise that patches will be accepted to lower the minimum required perl.

SYNOPSYS

use Data::Difference qw(data_diff);
use Data::Dumper;

my %from = (Q => 1, W => 2, E => 3, X => [1,2,3], Y=> [5,6]);
my %to = (W => 4, E => 3, R => 5, => X => [1,2], Y => [5,7,9]);
my @diff = data_diff(\%from, \%to);

@diff = (
  # value $a->{Q} was deleted
  { 'a'    => 1, 'path' => ['Q'] },

  # value $b->{R} was added
  { 'b'    => 5, 'path' => ['R'] },

  # value $a->{W} changed
  { 'a'    => 2, 'b'    => 4, 'path' => ['W'] },

  # value $a->{X}[2] was deleted
  { 'a'    => 3, 'path' => ['X', 2] },

  # value $a->{Y}[1] was changed
  { 'a'    => 6, 'b'    => 7, 'path' => ['Y', 1] },

  # value $b->{Y}[2] was added
  { 'b'    => 9, 'path' => ['Y', 2] },
);

AUTHOR

Graham Barr <gbarr@cpan.org>

COPYRIGHT

Copyright (c) 2011 Graham Barr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

AUTHOR

Graham Barr

CONTRIBUTORS

  • Graham Barr <gbarr@pobox.com>

  • Ricardo Signes <rjbs@semiotic.systems>

COPYRIGHT AND LICENSE

This software is copyright (c) 2025 by Graham Barr.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.