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ocamlinline-functions

How do I force OCaml to inline a function?

Is it possible to tell the OCaml compiler to inline a function, instead of hoping that its optimization process will do so itself?

Solution

  • You can both add an attribute to always inline a function

    let f x = x [@@inline always]
(* which is equivalent to *)
let f x = x [@@inline]

    or force a specific call to be inlined with another attribute

    let a = (f[@inlined]) 1

    If you want to check inlining decisions made by flambda, you can use the inlining-report flag.