Re: Copy an hash modifying some selected values

[hippo]

There will be a hatful of ways to approach this. Here's one using Data::DPath presented as an SSCCE:

use strict;
use warnings;

use Test::More tests => 1;
use Data::DPath 'dpathr';

my $home_path = '/home/foo';

my %hash1 = (
        key1 => 'relative_path',
        key2 => {
                key21 => 'another_relative_path',
                key22 => '/an_absolute_path',
                key23 => 'relative_path',
        },
        key3 => '',
        key4 => 4
);

my %hash2 = (
        key1 => "$home_path/relative_path",
        key2 => {
                key21 => 'another_relative_path',
                key22 => '/an_absolute_path',
                key23 => "$home_path/relative_path",
        },
        key3 => '',
        key4 => 4
);

my @list = ('/key1', '/key2/key22', '/key2/key23');

for my $keypat (@list) {
    foreach my $elem (dpathr ($keypat)->match (\%hash1)) {
        $$elem =~ s#^(?!/)#$home_path/#;
    };
}

is_deeply (\%hash1, \%hash2);

[Anonymous Monk]

Maybe I don't get it but to me this is comparing two hashes instead of searching into a hash a creating a copy of it with modifications where required.

[hippo]

Quite so. I assumed the copy was not the part you were having problems with. See eg merlyn's deep_copy sub as a module-less way to do that or something like Clone::PP. %hash1 is assumed to be the copy. HTH.