change integer layer field when 'l' is pressed

fcore/normal-mode.sml

@@ -226,10 +226,13 @@ struct
   fun updateNum (model: app_type, newNum) =
     (AppWith.modalNum (model, newNum), [])
 
+  fun clearNum model = updateNum (model, 0)
+
   fun updateRed model = (AppWith.r model, [])
   fun updateGreen model = (AppWith.g model, [])
   fun updateBlue model = (AppWith.b model, [])
   fun updateAlpha model = (AppWith.a model, [])
+  fun changeLayer model = (AppWith.layer model, [])
 
   fun selectCursorColour (model: app_type) =
     let
@@ -333,10 +336,12 @@ struct
     | MOUSE_LEFT_RELEASE => mouseMoveOrRelease model
     | MOUSE_LEFT_CLICK => mouseLeftClick model
     | NUM num => updateNum (model, num)
+    | KEY_ESC => clearNum model
     | KEY_R => updateRed model
     | KEY_G => updateGreen model
     | KEY_B => updateBlue model
     | KEY_A => updateAlpha model
+    | KEY_L => changeLayer model
     | KEY_C => selectCursorColour model
     | KEY_W => updateCanvasWidth model
     | KEY_H => updateCanvasHeight model
@@ -362,5 +367,4 @@ struct
     | KEY_SPACE => enterOrSpaceCoordinates model
     | FILE_BROWSER_AND_PATH {fileBrowser, path} =>
         handleFileBrowserAndPathInNormalMode (model, fileBrowser, path)
-    | KEY_ESC => (model, [])
 end

imperative-shell/input-callbacks.sml

@@ -58,13 +58,17 @@ struct
       key = Input.KEY_S () andalso action = Input.PRESS () andalso mods = 0x002
     then
       Mailbox.send (mailbox, KEY_CTRL_S)
+    else if
+      key = Input.KEY_L () andalso action = Input.PRESS () andalso mods = 0
+    then
+      Mailbox.send (mailbox, KEY_L)
     else if
       (* ctrl-l *)
       key = Input.KEY_L () andalso action = Input.PRESS () andalso mods = 0x002
     then
       Mailbox.send (mailbox, KEY_CTRL_L)
     else if
-      (* ctrl-l *)
+      (* ctrl-e *)
       key = Input.KEY_E () andalso action = Input.PRESS () andalso mods = 0x002
     then
       Mailbox.send (mailbox, KEY_CTRL_E)

message-types/input-msg.sml

@@ -16,6 +16,7 @@ struct
   | KEY_H
   | KEY_M
   | KEY_C
+  | KEY_L
   | KEY_BACKSPACE
   | KEY_CTRL_S
   | KEY_CTRL_L