reading JSON

FryingFinn has asked for the wisdom of the Perl Monks concerning the following question:

Hi Gang.

I just started w JSON. & I'm having a problem reading a simple? file.
I keep getting the error
"garbage after JSON object, at character offset 255 (before " "_id" : 1, "name" :...") at ./rd_students.pl line 12."

The json test file is ..

{ "_id" : 0, "name" : "Betty Boop",
             "subjects" : [
                { "type" : "optional", "subject" : "Voice"},
                { "type" : "required", "subject" : "Math" },
                { "type" : "required", "subject" : "English" } ]
}
{ "_id" : 1, "name" : "Donald Duck",
             "subjects" : [
                { "type" : "optional", "subject" : "Accounting" },
                { "type" : "required", "subject" : "Math" },
                { "type" : "required", "subject" : "English" } ]
}
[download]

The perl script..

#!/usr/bin/env perl
use JSON;
use Data::Dumper;
use Perl6::Slurp;
my $file = 'test.json';

my $json = slurp $file;

$text = decode_json($json);
print  Dumper($text);
[download]

Comment on reading JSON Select or Download Code

Replies are listed 'Best First'.
Re: reading JSON by neilwatson (Priest) on Jun 16, 2015 at 18:40 UTC
You have two documents in the json. They must be separated by commas and be in an array wrapped in []. `[ { "_id" : 0, "name" : "Betty Boop", "subjects" : [ { "type" : "optional", "subject" : "Voice"}, { "type" : "required", "subject" : "Math" }, { "type" : "required", "subject" : "English" } ] }, { "_id" : 1, "name" : "Donald Duck", "subjects" : [ { "type" : "optional", "subject" : "Accounting" }, { "type" : "required", "subject" : "Math" }, { "type" : "required", "subject" : "English" } ] } ]` [download] Neil Watson watson-wilson.ca	[reply] [d/l]
Re: reading JSON by jeffa (Bishop) on Jun 16, 2015 at 18:41 UTC
Try enclosing the whole structure into an array ref, and don't forget commas! `[ { "_id" : 0, "name" : "Betty Boop", "subjects" : [ { "type" : "optional", "subject" : "Voice"}, { "type" : "required", "subject" : "Math" }, { "type" : "required", "subject" : "English" } ] }, { "_id" : 1, "name" : "Donald Duck", "subjects" : [ { "type" : "optional", "subject" : "Accounting" }, { "type" : "required", "subject" : "Math" }, { "type" : "required", "subject" : "English" } ] } ]` [download] By the way, here is a utility i use to help debug JSON files: `alias djson='perl -MData::Dumper -MJSON -MFile::Slurp -e"print Dumper +decode_json read_file shift"'` [download] jeffa L-LL-L--L-LL-L--L-LL-L-- -R--R-RR-R--R-RR-R--R-RR B--B--B--B--B--B--B--B-- H---H---H---H---H---H--- (the triplet paradiddle with high-hat)	[reply] [d/l] [select]
Re^2: reading JSON by marinersk (Priest) on Jun 16, 2015 at 19:28 UTC
Nice one-liner. Thank you! `<pocketing />`	[reply] [d/l]