this post was submitted on 15 Sep 2024
22 points (77.5% liked)

Programming

17669 readers
187 users here now

Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!

Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.

Hope you enjoy the instance!

Rules

Rules

  • Follow the programming.dev instance rules
  • Keep content related to programming in some way
  • If you're posting long videos try to add in some form of tldr for those who don't want to watch videos

Wormhole

Follow the wormhole through a path of communities [email protected]

founded 2 years ago
MODERATORS
snowe
Ategon
[email protected]
22
RFC 7493: The I-JSON Message Format (datatracker.ietf.org)
submitted 3 months ago by lysdexic to c/programming
17 comments fedilink hide all child comments
you are viewing a single comment's thread
view the rest of the comments
[–] lysdexic 4 points 3 months ago* (last edited 3 months ago)

Why restrict to 54-bit signed integers?

Because number is a double, and IEEE754 specifies the mantissa of double-precision numbers as 53bits+sign.

Meaning, it's the highest integer precision that a double-precision object can express.

I suppose that makes sense for maximum compatibility, but feels gross if we’re already identifying value types.

It's not about compatibility. It's because JSON only has a number type which covers both floating point and integers, and number is implemented as a double-precision value. If you have to express integers with a double-precision type, when you go beyond 53bits you will start to experience loss of precision, which goes completely against the notion of an integer.