Math Extensions Proposal

• Spec

Champion

Rick Waldron

Status

This proposal is currently stage 1 of the TC39 process.

Motivation

These functions exist in many, many JS libraries either hand rolled or via many modules on npm. Providing them as built-ins serves to pave cow path. Implementations and naming is inconsistent. Several other languages offer these as built-ins.

Java

• https://docs.oracle.com/javase/7/docs/api/java/lang/Math.html
  • Math
    • Math.toDegrees(double angrad)
    • Math.toRadians(double angdeg)
• JSR275
  • Unit specification
• JScience

Python

• Math
  • https://docs.python.org/2/library/math.html#angular-conversion
  • https://docs.python.org/3/library/math.html#angular-conversion
    • math
      • math.degrees(x)
      • math.radians(x)
• Units

Racket

• Math
  • 4.2.2.10 Extra Constants and Functions
• Operations on Measures
  • 1.1.1 Operations on Measures

Rust

• https://doc.rust-lang.org/std/primitive.f32.html
• https://doc.rust-lang.org/std/primitive.f64.html

Questions

• Math.map
  • Is it...
    • Math.scale <-- this
    • Math.map
    • Math.remap
  • Should there be a corresponding Math.fmap? (ie. https://tc39.github.io/ecma262/#sec-math.fround, Step 3 & 4 convert result to IEEE 754-2008 binary32 (using roundTiesToEven), then to IEEE 754-2008 binary64).
• Math.constrain
  • Is it...
    • Math.constrain
    • Math.clamp

Polyfills

• Polyfill.
• Also, a polyfill is available in the core-js library. You can find it in the ECMAScript proposals section.