Re: [Json] on serialization of signed zero

Carsten Bormann <cabo@tzi.org> Sun, 05 July 2015 20:08 UTC

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Date: Sun, 05 Jul 2015 22:08:33 +0200
From: Carsten Bormann <cabo@tzi.org>
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Subject: Re: [Json] on serialization of signed zero
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Phillip Hallam-Baker wrote:
> Same as NaN, you can't.

Not the same.

There is no representation for NaN in JSON.
(The usual recommendation is to substitute `null`.)
The reason is as arcane as it is frustrating:
JavaScript handles NaN etc. using variables, so there is no syntax in
the JavaScript value notation that became JSON.

There are a number of representations for negative zeros.

JavaScript can even properly parse and decode them, e.g.:

JSON.parse("-0")
-0

It just can't roundtrip them:

JSON.stringify(-0)
"0"

So if it is indeed important for you to be able to roundtrip negative
zeros through JavaScript, you'll need to invent something.
Such as representing negative zero by a string, "-0".
(JavaScript can roundtrip those, but of course you are on your own in
decoding them.)

Grüße, Carsten

[Json] on serialization of signed zero Sonny Piers
Re: [Json] on serialization of signed zero Phillip Hallam-Baker
Re: [Json] on serialization of signed zero Carsten Bormann
Re: [Json] on serialization of signed zero Tim Bray
Re: [Json] on serialization of signed zero Carsten Bormann