Joseph Ferano
7ce6043c47
sort-i32! was the only sort in the language. sort-f32! and sort-bytes! are the other two, and they are copies rather than an abstraction for a reason worth naming precisely: map, filter, reduce and a sort taking a comparator are not blocked on generics, they are blocked on *function values*. Types.Fn exists and check.ml refuses it with "a function type is not implemented yet -- milestone 5", and there is nothing else in the language to pass. Generics on top of that is what would make them one copy instead of one per element type. The f32 family carries one caveat the i32 family cannot have: a NaN makes the order undefined, because every comparison against one is false, so the insertion loop never moves it and never moves anything past it. sum-f32 accumulates in f64 for a stronger version of sum-i32's argument -- an f32 total does not wrap, it absorbs, and the answer comes out silently short. The test prints the difference rather than the total, because %g hides it. sort-bytes! is the one a caller of split actually wants, and its ordering is memcmp's: bytewise, unsigned, prefix first. Not alphabetical -- "Zebra" sorts before "apple" -- and the note says so, for the same reason the ASCII-case note refuses a locale. The slices move and the bytes never do, so it sorts fields borrowed out of a string literal, which an in-place byte sort could not.
