JSON.parse()

[espruino-discuss]

Posted at 2014-03-26 by Sacha

Hi,

Have some problem with JSON.parse.

test={};
test['myname']='ESP:33FFD705-41573033-27620843';
test['first']={"pin":A15};

console.log('Orig:');
console.log(test);

json=JSON.stringify(test);

console.log('JSON:');
console.log(json);

console.log('Back:');
console.log(JSON.parse(json));

Here is the output:

Orig:
{
  "myname":"ESP:33FFD705-41573033-27620843",
  "first":{"pin":A15}
}
JSON:
{"myname":"ESP:33FFD705-41573033-27620843","first":{"pin":A15}}
Back:
undefined
=undefined

Back is undefined. I expected the same as 'test'.

Thanks
Sacha

[espruino-discuss]

Posted at 2014-03-27 by Sacha

It should work like this:

http://jsconsole.com/?var%20A15%3D%22ok%22%3B%0A%0Atest%3D%7B%7D%3B%0Atest%5B%27myname%27%5D%3D%27ESP%3A33FFD705-41573033-27620843%27%3B%0Atest%5B%27first%27%5D%3D%7B%22pin%22%3AA15%7D%3B%0A%0Aconsole.log(%27Orig%3A%27)%3B%0Aconsole.log(test)%3B%0A%0Ajson%3DJSON.stringify(test)%3B%0A%0Aconsole.log(%27JSON%3A%27)%3B%0Aconsole.log(json)%3B%0A%0Aconsole.log(%27Back%3A%27)%3B%0Aconsole.log(JSON.parse(json))%3B

Sacha

[gfwilliams]

Posted at 2014-03-27 by @gfwilliams

Thanks. This'll be an issue with JSON.stringify rather than JSON.parse (which is now adhering to the spec). If you want to work around it, use eval("("+json+")").

It's that pins are output as just pins - but obviously JSON has no idea about pins so when they are encountered it just returns 'undefined'.

[gfwilliams]

Posted at 2014-03-27 by @gfwilliams

I've made a bug for this so i'll see what I can do about fixing it

[espruino-discuss]

Posted at 2014-03-27 by Sacha

Thanks Gordon for the workaround.

Could it be that when i implement it right know with eval, that this won't work anymore after you fixed it on the "stringify" side ?

Sacha

[gfwilliams]

Posted at 2014-03-27 by @gfwilliams

Well, I was trying to think of a way around this - possibly converting the pin to an integer - which would work fine for digitalWrite/etc - the only problem would be if you tried to use a pin.read/write/set/reset