oxc/approx-constant

Typing 3.14159 by hand is less precise than Math.PI, and readers have to recognize the digits to know what it is.

The rule reports a number with at least three decimals that's a cut off or rounded Math.E, Math.LN10, Math.LN2, Math.LOG2E, Math.LOG10E, Math.PI, Math.SQRT1_2 or Math.SQRT2. 3.14 is too short to count.

--fix-suggestions replaces the number with the constant.

Configure

Off by default. To turn it on:

[lint.rules]
"oxc/approx-constant" = "error" # or "warn"

Examples

Reported:

function circleArea(radius) {
  return 3.14159 * radius * radius;
}

const diagonal = side * 1.4142;

Not reported:

function circleArea(radius) {
  return Math.PI * radius * radius;
}

const diagonal = side * Math.SQRT2;
const price = 3.14;