avoid rec when called with a negative argument

device-usage/block/unikernel.ml

@@ -45,7 +45,7 @@ module Main (Time : Mirage_time.S) (B : Mirage_block.S) = struct
 
   let alloc sector_size n =
     let rec loop = function
-      | 0 -> []
+      | n when (n<=0) -> []
       | n ->
           let page = Io_page.(to_cstruct (get 1)) in
           let phrase =

device-usage/console/unikernel.ml

@@ -3,7 +3,7 @@ open Lwt.Infix
 module Main (C : Mirage_console.S) (Time : Mirage_time.S) = struct
   let start c _time =
     let rec loop = function
-      | 0 -> Lwt.return_unit
+      | n when (n<=0) -> Lwt.return_unit
       | n ->
           C.log c "hello" >>= fun () ->
           Time.sleep_ns (Duration.of_sec 1) >>= fun () ->

tutorial/hello-key/unikernel.ml

@@ -5,7 +5,7 @@ module Hello (Time : Mirage_time.S) = struct
     let hello = Key_gen.hello () in
 
     let rec loop = function
-      | 0 -> Lwt.return_unit
+      | n when (n<=0) -> Lwt.return_unit
       | n ->
           Logs.info (fun f -> f "%s" hello);
           Time.sleep_ns (Duration.of_sec 1) >>= fun () -> loop (n - 1)

tutorial/hello/unikernel.ml

@@ -3,7 +3,7 @@ open Lwt.Infix
 module Hello (Time : Mirage_time.S) = struct
   let start _time =
     let rec loop = function
-      | 0 -> Lwt.return_unit
+      | n when (n<=0) -> Lwt.return_unit
       | n ->
           Logs.info (fun f -> f "hello");
           Time.sleep_ns (Duration.of_sec 1) >>= fun () -> loop (n - 1)

tutorial/lwt/echo_server/unikernel.ml

@@ -13,7 +13,7 @@ struct
 
   let start c _time _r =
     let rec echo_server = function
-      | 0 -> Lwt.return ()
+      | n when (n<=0) -> Lwt.return ()
       | n ->
           read_line () >>= fun s ->
           C.log c s >>= fun () -> echo_server (n - 1)