ctx.arc(center=Point(10,20), radius=30, beginAngle=0, endAngle=6.28, Clockwise);

https://stackoverflow.com/questions/107243/are-units-of-meas...

    ctx.arc(center=Point(10cm,20cm), radius=30mm, beginAngle=0rad, endAngle=6.28rad, Clockwise);

I'd like to be able to say the end angle has to be less than the start angle, that the unit has to be radians (AKA unit-less :), the unit of radius & that negative values are sensical, and so forth; and have all these properties checked by a compiler.

Which I can do in some modern languages, surprisingly. :)

   data Directionality = Clockwise | Anticlockwise

   data AngularInterval = {
     beginAngle :: Double,
     endAngle :: Double,
     directionality :: Directionality
   }

But I know what you're getting at! Personally, I'm a fan of programming with units and dimensions, and safely representing the distinction between absolute quantities and relative quantities.

That doesn't mean I'd want an infinite number of "float" values for all possible units and dimensions, however; just a powerful enough type system I can give myself some help at compile-time for properly threading sensical values through my programs.

But we use plenty of literals in our programs all the time. Eg lambdas are function literals. (And definitions of named functions are just a special case folding binding and a lambda.)