++Corion, and so if you want ordered pairs (same rules for json as Perl), the most obvious treatment is to replace that hash with an array of little hashes, e.g.:
use strict;
use warnings;

binmode STDOUT, ":utf8";
use utf8;

use JSON;

my $json ={
    'book' => [
        {'title' => 'smth'},
        {'num_page' => 234}
    ]
};
open my $fh, ">", "data_out.json";
print $fh encode_json($json);
close $fh;

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Alternatively, you could sort the hash keys on the receiving end in Javascript into a particular order (put the key names in another hash with the sort positions as values for use in a sort function in Javascript) but that would be outside the scope of the monastery.

One world, one people

In reply to Re^3: Write json structure to a file by anonymized user 468275
in thread Write json structure to a file by CropCircle

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