Implement: onfail, onsuccess, onrun, log_program_output, mailto.

[goaljobs.git] / pa_goal.ml

diff --git a/pa_goal.ml b/pa_goal.ml
index 86f67db..e795233 100644 (file)
--- a/pa_goal.ml
+++ b/pa_goal.ml
@@ -84,7 +84,44 @@ let generate_let_goal _loc (r : rec_flag) (lets : binding) =
       );
 
       (* Put a try-clause around the body. *)
-      let body = <:expr< try $body$ with Goal_result Goal_OK -> () >> in
+      let body = <:expr<
+        (* Define a goal name which the body may use. *)
+        let goalname = $str:name$ in
+        (* Define onsuccess, onrun, onfail functions that the body may call. *)
+        let _on, _call_on =
+          let _on fns f = fns := f :: !fns in
+          let _call_on fns a = List.iter (fun f -> f a) !fns in
+          _on, _call_on
+        in
+        let onfail, _call_onfails =
+          let fns = ref [] in (_on fns), (_call_on fns)
+        in
+        let onrun, _call_onruns =
+          let fns = ref [] in (_on fns), (_call_on fns)
+        in
+        let onsuccess, _call_onsuccesses =
+          let fns = ref [] in (_on fns), (_call_on fns)
+        in
+
+        try
+          $body$ ;
+          _call_onruns ();
+          _call_onsuccesses ();
+
+          (* Avoid a compiler warning: *)
+          ignore (goalname)
+        with
+        (* target() within the body may raise Goal_OK meaning that the
+         * goal should be short-circuited.  We return as if it's an
+         * ordinary function exit.
+         *)
+        | Goal_result Goal_OK ->
+          _call_onsuccesses ();
+          ()
+        | exn ->
+          _call_onfails exn;
+          raise exn
+      >> in
 
       (* Recreate the function with parameters. *)
       let expr =