Support more types in switch conditions

[trusktr]

I've got some variables all of the same type, and I'm trying to use them in a switch, something like:

const f: f64 = 1.3
const g: f64 = 2.4

switch(f) {
  case g: ...; break
}

but it result in an error like

ERROR AS200: Conversion from type 'f64' to 'u32' requires an explicit cast.

Here's the whole code:

	getHSL(target: HSL): HSL {
		// h,s,l ranges are in 0.0 - 1.0

		const r: f64 = this.r,
			g: f64 = this.g,
			b: f64 = this.b

		let max: f64 = Math.max(r, g)
		max = Math.max(max, b)

		let min: f64 = Math.max(r, g)
		min = Math.min(min, b)

		let hue: f64 = 0
		let saturation: f64 = 0
		const lightness: f64 = (min + max) / 2.0

		if (min === max) {
			hue = 0
			saturation = 0
		} else {
			const delta = max - min

			saturation = lightness <= 0.5 ? delta / (max + min) : delta / (2 - max - min)

			switch (max) {
				case r:
					hue = (g - b) / delta + (g < b ? 6 : 0)
					break
				case g:
					hue = (b - r) / delta + 2
					break
				case b:
					hue = (r - g) / delta + 4
					break
			}

			hue /= 6
		}

		target.h = hue
		target.s = saturation
		target.l = lightness

		return target
	}

and the error output:

ERROR AS200: Conversion from type 'f64' to 'u32' requires an explicit cast.

                        switch (max) {
            ~~~
 in src/as/glas/math/Color.ts(559,11)

ERROR AS200: Conversion from type 'f64' to 'u32' requires an explicit cast.

                                case r:
          ~
 in src/as/glas/math/Color.ts(560,9)

ERROR AS200: Conversion from type 'f64' to 'u32' requires an explicit cast.

                                case g:
          ~
 in src/as/glas/math/Color.ts(563,9)

ERROR AS200: Conversion from type 'f64' to 'u32' requires an explicit cast.

                                case b:
          ~
 in src/as/glas/math/Color.ts(566,9)

[willemneal]

Hmm, I've never encountered switching on a floating point number before. I'm not sure it's well specified since floating point equality is not precise. I would switch to using if/elses.

[trusktr]

That's what I ended up doing, but seems like the switch should use the same underlying equality check (probably using ==).

But even with conditionals, I'm having problems with the above code, I'm porting the code (and its tests) from JS to AS, but in AS I'm getting different values, and the tests are failing.

[MaxGraey]

You could rewrite it to:

switch (true) {
  case max == r:
    hue = (g - b) / delta + (g < b ? 6 : 0)
    break
  case max == g:
    hue = (b - r) / delta + 2
    break
  case max == b:
    hue = (r - g) / delta + 4
    break
}

[ColinEberhardt]

+1 for supporting switch/case with string values