I've experimented on a few systems to apply interval arithmetic to type inference, i.e. // starRating is an int<0,5>, meaning // integer between 0 and 5

I've experimented on a few systems to apply interval arithmetic to type inference, i.e. // starRating is an int<0,5>, meaning // integer between 0 and 5 inclusive. let starRating = console.readInt<0,5>("How many stars do you rate this movie?"); db.addStarRating(starRating); // starRatingList is a list<int<0,5>> let starRatingList = db.readStarRatings(movie); // totalStarRatings is an int<0,5*starRatingList.length> // this type can't be sized at compile time, but we can still check it! let totalStarRatings = sum(starRatings); // avgStarRating is a very difficult type, because we need to either have // a fraction type that's slow, or some handling of rounding/truncating // when we do division. So now we're dealing with 3 intervals: min/max, // min/max precision, and min/max error. let avgStarRating = totalStarRatings / starRatingList.length;