Hi all, I am new to programming and Perl. I am using a an API to return JSON data/array/hash and from that I need to create a variable from part of the data in order to create my next URL. From a previous request for help I have been advised that I should use the JSON module. I have tried to follow an example taken from google, but clearly failing to grasp the program logic or syntax. 

#!/usr/bin/perl
use warnings;
use strict;
use WebService::Tesco::API;
use JSON;

# My code to login removed


print "Scan Item....";
my $pn = <>;                                          #Scan Bar Code
chop ($pn);                                                          #
+remove %OA from end of scan code

my $code = $tesco->product_search({ searchtext => $pn, extendedinfo =>
+ 'N' });

my $json = JSON->new;
my $data = $json->decode($code);

my $pid = $data->{Products}[0]{ProductId},"\n";

print $pid,"\n";

[download]

Returned is: 

Useless use of a constant (
) in void context at tesc_json1.pl line 22.
https://secure.techfortesco.com/groceryapi_b1/restservice.aspx?email=x
+xxxx%40yahoo.co.uk&password=xxxxx&developerkey=xxxxxx&applicationkey=
+xxxxx&command=LOGIN at /usr/local/share/perl/5.14.2/WebService/Tesco/
+API.pm line 59.
{
"StatusCode": 0,
"StatusInfo": "Command Processed OK",
"BranchNumber": "5528",
"CustomerId": "20846164",
"CustomerName": "Mr Stubbs",
"SessionKey": "5VApkMMTjO8LtFCy9VjcSrcZKxoewwHGj6XoUUGaH2fBWf73cU",
"InAmendOrderMode": "N",
"BasketID": "98911496",
"ChosenDeliverySlotInfo": "No delivery slot is reserved.",
"CustomerForename": "James"
}
Scan Item....5000175411118
http://www.techfortesco.com/groceryapi_b1/restservice.aspx?searchtext=
+5000175411118&extendedinfo=N&sessionkey=5VApkMMTjO8LtFCy9VjcSrcZKxoew
+wHGj6XoUUGaH2fBWf73cU&command=PRODUCTSEARCH at /usr/local/share/perl/
+5.14.2/WebService/Tesco/API.pm line 59, <> line 1.
{
"StatusCode": 0,
"StatusInfo": "Command Processed OK",
"PageNumber": 0,
"TotalPageCount": 1,
"TotalProductCount": 1,
"PageProductCount": 1,
"Products":
[
{
"BaseProductId": "50043662",
"EANBarcode": "5000175411118",
"CheaperAlternativeProductId": "",
"HealthierAlternativeProductId": "",
"ImagePath": "http://img.tesco.com/Groceries/pi/118/5000175411118/IDSh
+ot_90x90.jpg",
"MaximumPurchaseQuantity": 99,
"Name": "Oxo 12 Chicken Stock Cubes 71G",
"OfferPromotion": "Price Drop Was £1.13 Now £1.00 ",
"OfferValidity": "valid from 30/7/2012 until 9/9/2012",
"OfferLabelImagePath": "http://www.tesco.com/Groceries/UIAssets/I/Site
+s/Retail/Superstore/Online/Product/pos/save.png",
"Price": 1,
"PriceDescription": "£1.41 each",
"ProductId": "254881114",
"ProductType": "QuantityOnlyProduct",
"UnitPrice": 1.41,
"UnitType": "100g"
}
]
}
malformed JSON string, neither array, object, number, string or atom, 
+at character offset 0 (before "HASH(0x1610440)") at tesc_json1.pl lin
+e 20, <> line 1.

[download]

Clearly I have two (2) errors, despite googling, I am unable figure out what it is I am doing wrong. I would appreciate it if someone could assist.

Thank you - James

In reply to Help with JSON Module by foggy3657

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