globals are now variable

1 files changed, 18 insertions, 1 deletions

diff --git a/vm.c b/vm.c
index 00ba397..9f6ece6 100644
--- a/vm.c
+++ b/vm.c
@@ -56,6 +56,7 @@ void runvm(State *S) {
 
 #define PUSH(v) th->stack[th->sp++] = v;
 #define POP()   (th->stack[--th->sp])
+#define PEEK()  (th->stack[th->sp-1])
 
 	puts("---");
 	while (1) {
@@ -75,7 +76,10 @@ void runvm(State *S) {
 			break;
 		}
 		case OP_PRINT:
-			println_val(POP());
+			println_val(PEEK());
+			break;
+		case OP_DROP:
+			--th->sp;
 			break;
 
 		case OP_GETGLOBAL: {
@@ -90,6 +94,19 @@ void runvm(State *S) {
 			PUSH(v);
 			break;
 		}
+		case OP_SETGLOBAL: {
+			uint8_t cix = RBYTE();
+			Val varname = ch->consts.d[cix];
+			if (!IS_STRING(varname)) {
+				printf("global names must be string, not %s\n",
+					typename_str(varname));
+				goto done;
+			}
+			Val v = PEEK();
+
+			ht_put(S, &S->globals, AS_STRING(varname), v);
+			break;
+		}
 
 #define ARITH_OP(opcode, OP) \
 		case opcode: { \