1 files changed, 66 insertions, 2 deletions

diff --git a/src/interactive.ml b/src/interactive.ml
index 12a1be64..0fad3caf 100644
--- a/src/interactive.ml
+++ b/src/interactive.ml
@@ -48,21 +48,85 @@
 (*  SUCH DAMAGE.                                                          *)
 (**************************************************************************)
 
+open Ast
+open Ast_util
+open Printf
+   
 let opt_interactive = ref false
 let opt_emacs_mode = ref false
 let opt_suppress_banner = ref false
 
 let env = ref Type_check.initial_env
 
-let ast = ref (Ast.Defs [])
+let ast = ref (Defs [])
 
 let arg str =
   ("<" ^ str ^ ">") |> Util.yellow |> Util.clear
 
 let command str =
-  (":" ^ str) |> Util.green |> Util.clear
+  str |> Util.green |> Util.clear
+
+type action =
+  | ArgString of string * (string -> action)
+  | ArgInt of string * (int -> action)
+  | Action of (unit -> unit)
 
 let commands = ref []
+            
+let reflect_typ action =
+  let open Type_check in
+  let rec arg_typs = function
+    | ArgString (_, next) -> string_typ :: arg_typs (next "")
+    | ArgInt (_, next) -> int_typ :: arg_typs (next 0)
+    | Action _ -> []
+  in
+  function_typ (arg_typs action) unit_typ no_effect
+
+let generate_help name help action =
+  let rec args = function
+    | ArgString (hint, next) -> arg hint :: args (next "")
+    | ArgInt (hint, next) -> arg hint :: args (next 0)
+    | Action _ -> []
+  in
+  let args = args action in
+  let help = match String.split_on_char ':' help with
+    | [] -> assert false
+    | (prefix :: splits) ->
+       List.map (fun split ->
+           match String.split_on_char ' ' split with
+           | [] -> assert false
+           | (subst :: rest) ->
+              if Str.string_match (Str.regexp "^[0-9]+") subst 0 then
+                let num_str = Str.matched_string subst in
+                let num_end = Str.match_end () in
+                let punct = String.sub subst num_end (String.length subst - num_end) in
+                List.nth args (int_of_string num_str) ^ punct ^ " " ^ String.concat " " rest
+              else
+                command (":" ^ subst) ^ " " ^ String.concat " " rest
+         ) splits
+       |> String.concat ""
+       |> (fun rest -> prefix ^ rest)
+  in
+  sprintf "%s %s - %s" Util.(name |> green |> clear) (String.concat ", " args) help
 
+let run_action cmd argument action =
+  let args = String.split_on_char ',' argument in
+  let rec call args action =
+    match args, action with
+    | (x :: xs), ArgString (hint, next) ->
+       call xs (next (String.trim x))
+    | (x :: xs), ArgInt (hint, next) ->
+       let x = String.trim x in
+       if Str.string_match (Str.regexp "^[0-9]+$") x 0 then
+         call xs (next (int_of_string x))
+       else
+         print_endline (sprintf "%s argument %s must be an non-negative integer" (command cmd) (arg hint))
+    | _, Action act ->
+       act ()
+    | _, _ ->
+       print_endline (sprintf "Bad arguments for %s, see (%s %s)" (command cmd) (command ":help") (command cmd))
+  in
+  call args action
+  
 let register_command ~name:name ~help:help action =
   commands := (":" ^ name, (help, action)) :: !commands