Slight internal representation change of string-only exceptions.

One upshot of all this is that (throw 'foo "msg") now
does exactly the same thing as (throwf 'foo "msg").
A message-only exception really is a one-string exception argument
list ("message ..."), like the documentation says.

* unwind.h (struct uw_catch): exception member renamed to args.
(uw_catch): Macro follows structure member rename.

* eval.c (op_catch): Removed now unnecessary kludge of turning non-list
exception argument list into a one-element argument list.

* match.c (v_try): Similar hack to the one in op_catch
removed here.

* unwind.c (uw_unwind_to_exit_point, uw_push_catch): Follows rename of
exception member.
(uw_throw): The exception parameter is renamed to args.  The kludge
removed from op_catch re-appears here, because numerous calls
to uw_throw just pass a string as args. It's less of a kludge here
because this is the master entry point to exception processing,
and it straightens out the representation right away.
The exception arguments or message are printed in a clearer way.

1 files changed, 1 insertions, 3 deletions

diff --git a/eval.c b/eval.c
index 7e27c962..056f4b68 100644
--- a/eval.c
+++ b/eval.c
@@ -2002,9 +2002,7 @@ static val op_catch(val form, val env)
       if (uw_exception_subtype_p(exsym, type)) {
         val params = second(clause);
         val saved_de = set_dyn_env(make_env(nil, nil, dyn_env));
-        val clause_env = bind_args(env, params, if3(listp(exvals),
-                                                    exvals, cons(exvals, nil)),
-                                   clause);
+        val clause_env = bind_args(env, params, exvals, clause);
         result = eval_progn(rest(rest(clause)), clause_env, clause);
         set_dyn_env(saved_de);
         break;