unikernel/duniverse/dune_/otherlibs/ordering/ordering.ml

@@ -0,0 +1,51 @@
+type t =
+  | Lt
+  | Eq
+  | Gt
+
+let of_int n = if n < 0 then Lt else if n = 0 then Eq else Gt
+
+let to_int = function
+  | Lt -> -1
+  | Eq -> 0
+  | Gt -> 1
+;;
+
+let to_string = function
+  | Lt -> "<"
+  | Eq -> "="
+  | Gt -> ">"
+;;
+
+let is_eq = function
+  | Eq -> true
+  | Lt | Gt -> false
+;;
+
+let min f x y =
+  match f x y with
+  | Eq | Lt -> x
+  | Gt -> y
+;;
+
+let max f x y =
+  match f x y with
+  | Eq | Gt -> x
+  | Lt -> y
+;;
+
+let opposite = function
+  | Lt -> Gt
+  | Eq -> Eq
+  | Gt -> Lt
+;;
+
+let reverse f a b = opposite (f a b)
+
+module O = struct
+  let ( let= ) t f =
+    match t with
+    | (Lt | Gt) as result -> result
+    | Eq -> f ()
+  ;;
+end