To add to your good comment, doing inlining intelligently can get tricky in language using a lot of polymorphic functions like Ocaml. To squeeze out performanc

To add to your good comment, doing inlining intelligently can get tricky in language using a lot of polymorphic functions like Ocaml. To squeeze out performance, you have to detect when polymorphic functions are actually used on int and decide if you want to compile and store a special cased version which avoid the unboxing-boxing shuffle. There is a balance to find between compile time, program size and speed of running code which is fairly hard to get right.