maki
Persistent incremental computations, for repeatable tests and benchmarks.
Status: beta
For more details, see the initial design document (obsolete) and the blog post
Examples
Simple memoizing of a recursive function
let fib =
let rec fib n = Maki.(
mk1 ~name:"fib" Hash.int Codec.int ~lifetime:Lifetime.one_minute
~f:(fun x -> if x <= 1
then return_ok 1
else (fib (x-1) >>= fun x1 ->
fib (x-2) >|= fun x2 -> x1+x2))
n
) in
fib;;
fib 42 ;;
(* returns [Ok 42] *)Concatenating file, but memoizing the result as long as they do not change
open Lwt.Infix;;
let concat =
Maki.(mk2 ~name:"concat" Hash.file_ref Hash.file_ref Codec.string ~lifetime:Lifetime.one_hour
~f:(fun f1 f2 ->
let open E in
read_file f1 >>= fun content1 ->
read_file f2 >>= fun content2 ->
return_ok (content1 ^ content2)))
;;
let x1 = Maki.(File_ref.make "foo1" >>= fun f1 -> File_ref.make "foo2" >>= concat f1);;
(* cached *)
let x2 = Maki.(File_ref.make "foo1" >>= fun f1 -> File_ref.make "foo2" >>= concat f1);;
(* now change contnet of file "foo1", so this should change too *)
let x3 = Maki.(File_ref.make "foo1" >>= fun f1 -> File_ref.make "foo2" >>= concat f1);;