altos/lisp: Separate out values from atoms

This enables changing values of atoms declared as constants, should
enable lets, and with some work, even lexical scoping.

this required changing the constant computation to run
ao_lisp_collect() before dumping the block of constant data, and that
uncovered some minor memory manager bugs.

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

1 files changed, 28 insertions, 9 deletions

diff --git a/src/lisp/ao_lisp_builtin.c b/src/lisp/ao_lisp_builtin.c
index 63fb69fd..8c481793 100644
--- a/src/lisp/ao_lisp_builtin.c
+++ b/src/lisp/ao_lisp_builtin.c
@@ -14,6 +14,31 @@
 
 #include "ao_lisp.h"
 
+static int
+builtin_size(void *addr)
+{
+	(void) addr;
+	return sizeof (struct ao_lisp_builtin);
+}
+
+static void
+builtin_mark(void *addr)
+{
+	(void) addr;
+}
+
+static void
+builtin_move(void *addr)
+{
+	(void) addr;
+}
+
+const struct ao_lisp_type ao_lisp_builtin_type = {
+	.size = builtin_size,
+	.mark = builtin_mark,
+	.move = builtin_move
+};
+
 void
 ao_lisp_builtin_print(ao_poly b)
 {
@@ -120,20 +145,12 @@ ao_lisp_quote(struct ao_lisp_cons *cons)
 ao_poly
 ao_lisp_set(struct ao_lisp_cons *cons)
 {
-	ao_poly	atom, val;
 	if (!check_argc(cons, 2, 2))
 		return AO_LISP_NIL;
 	if (!check_argt(cons, 0, AO_LISP_ATOM, 0))
 		return AO_LISP_NIL;
 
-	atom = cons->car;
-	val = ao_lisp_poly_cons(cons->cdr)->car;
-	if (ao_lisp_is_const(atom)) {
-		ao_lisp_exception |= AO_LISP_INVALID;
-		return AO_LISP_NIL;
-	}
-	ao_lisp_poly_atom(atom)->val = val;
-	return val;
+	return ao_lisp_atom_set(cons->car, ao_lisp_poly_cons(cons->cdr)->car);
 }
 
 ao_poly
@@ -157,6 +174,8 @@ ao_lisp_print(struct ao_lisp_cons *cons)
 		val = cons->car;
 		ao_lisp_poly_print(val);
 		cons = ao_lisp_poly_cons(cons->cdr);
+		if (cons)
+			printf(" ");
 	}
 	return val;
 }