Create std::units module (#6528)

Signed-off-by: Nick Cameron <nrc@ncameron.org>

rust/kcl-lib/std/units.kcl

@@ -0,0 +1,68 @@
+@no_std
+@settings(defaultLengthUnit = mm)
+
+/// Convert a number to millimeters from its current units.
+export fn toMillimeters(@num: number(mm)): number(mm) {
+  return num
+}
+
+/// Convert a number to centimeters from its current units.
+export fn toCentimeters(@num: number(cm)): number(cm) {
+  return num
+}
+
+/// Convert a number to meters from its current units.
+export fn toMeters(@num: number(m)): number(m) {
+  return num
+}
+
+/// Convert a number to inches from its current units.
+export fn toInches(@num: number(in)): number(in) {
+  return num
+}
+
+/// Convert a number to feet from its current units.
+export fn toFeet(@num: number(ft)): number(ft) {
+  return num
+}
+
+/// Converts a number to yards from its current units.
+export fn toYards(@num: number(yd)): number(yd) {
+  return num
+}
+
+/// Converts a number to radians from its current units.
+///
+/// ```
+/// exampleSketch = startSketchOn(XZ)
+///   |> startProfile(at = [0, 0])
+///   |> angledLine(
+///     angle = 50,
+///     length = 70 * cos(units::toRadians(45)),
+///   )
+///   |> yLine(endAbsolute = 0)
+///   |> close()
+///
+/// example = extrude(exampleSketch, length = 5)
+/// ```
+export fn toRadians(@num: number(rad)): number(rad) {
+  return num
+}
+
+/// Converts a number to degrees from its current units.
+///
+/// ```
+/// exampleSketch = startSketchOn(XZ)
+///   |> startProfile(at = [0, 0])
+///   |> angledLine(
+///     angle = 50,
+///     length = 70 * cos(units::toDegrees((PI/4): number(rad))),
+///   )
+///   |> yLine(endAbsolute = 0)
+///   |> close()
+///
+/// example = extrude(exampleSketch, length = 5)
+/// ```
+export fn toDegrees(@num: number(deg)): number(deg) {
+  return num
+}