altos/lisp: split set/def. Add def support to lambdas

In scheme, set can only re-define existing variables while def cannot
redefine existing variables in lambda context. Def within lambda
creates a new variable at the nearest enclosing scope.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/lisp/ao_lisp_eval.c b/src/lisp/ao_lisp_eval.c
index fa25edf0..02329ee6 100644
--- a/src/lisp/ao_lisp_eval.c
+++ b/src/lisp/ao_lisp_eval.c
@@ -559,6 +559,8 @@ ao_lisp_eval(ao_poly _v)
 {
 	ao_lisp_v = _v;
 
+	ao_lisp_frame_init();
+
 	if (!ao_lisp_stack_push())
 		return AO_LISP_NIL;