compiler support for tuple expressions

chunk.h

@@ -70,6 +70,7 @@ typedef enum {
 
 	OP_EXPAND_ARGS,
 	OP_FINALIZE,
+	OP_TUPLE,
 
 	OP_CONSTANT_LONG = 128,
 	OP_DEFINE_GLOBAL_LONG,
@@ -89,6 +90,7 @@ typedef enum {
 	OP_GET_SUPER_LONG,
 	OP_INC_LONG,
 	OP_KWARGS_LONG,
+	OP_TUPLE_LONG,
 } KrkOpCode;
 
 typedef struct {

compiler.c

@@ -1351,7 +1351,21 @@ static void statement() {
 
 static void grouping(int canAssign) {
 	startEatingWhitespace();
-	expression();
+	if (check(TOKEN_RIGHT_PAREN)) {
+		emitBytes(OP_TUPLE,0);
+	} else {
+		expression();
+		if (match(TOKEN_COMMA)) {
+			size_t argCount = 1;
+			if (!check(TOKEN_RIGHT_PAREN)) {
+				do {
+					expression();
+					argCount++;
+				} while (match(TOKEN_COMMA) && !check(TOKEN_RIGHT_PAREN));
+			}
+			EMIT_CONSTANT_OP(OP_TUPLE, argCount);
+		}
+	}
 	stopEatingWhitespace();
 	consume(TOKEN_RIGHT_PAREN, "Expect ')' after expression.");
 }

debug.c

@@ -116,6 +116,7 @@ size_t krk_disassembleInstruction(KrkChunk * chunk, size_t offset) {
 		OPERAND(OP_GET_UPVALUE)
 		OPERAND(OP_CALL)
 		OPERAND(OP_INC)
+		OPERAND(OP_TUPLE)
 		JUMP(OP_JUMP,+)
 		JUMP(OP_JUMP_IF_FALSE,+)
 		JUMP(OP_JUMP_IF_TRUE,+)

vm.c

@@ -1876,11 +1876,16 @@ static KrkValue _bound_get_file(int argc, KrkValue argv[]) {
 	return _closure_get_file(1, (KrkValue[]){OBJECT_VAL(boundMethod->method)});
 }
 
-/* tuple.__init__ */
 static KrkValue _tuple_init(int argc, KrkValue argv[]) {
-	KrkTuple * self = krk_newTuple(argc-1);
+	krk_runtimeError(vm.exceptions.typeError,"tuple() initializier unsupported");
+	return NONE_VAL();
+}
+
+/* tuple creator */
+static KrkValue _tuple_of(int argc, KrkValue argv[]) {
+	KrkTuple * self = krk_newTuple(argc);
 	krk_push(OBJECT_VAL(self));
-	for (size_t i = 1; i < (size_t)argc; ++i) {
+	for (size_t i = 0; i < (size_t)argc; ++i) {
 		self->values.values[self->values.count++] = argv[i];
 	}
 	krk_pop();
@@ -1948,6 +1953,11 @@ static KrkValue _tuple_repr(int argc, KrkValue argv[]) {
 		}
 	}
 
+	if (tuple->values.count == 1) {
+		krk_push(OBJECT_VAL(S(",")));
+		addObjects();
+	}
+
 	krk_push(OBJECT_VAL(S(")")));
 	addObjects();
 	tuple->inrepr = 0;
@@ -3263,6 +3273,21 @@ static KrkValue run() {
 				krk_push(KWARGS_VAL(readBytes(frame,operandWidth)));
 				break;
 			}
+			case OP_TUPLE_LONG:
+			case OP_TUPLE: {
+				size_t count = readBytes(frame, operandWidth);
+				KrkValue tuple = _tuple_of(count,&vm.stackTop[-count]);
+				if (count) {
+					vm.stackTop[-count] = tuple;
+					while (count > 1) {
+						krk_pop();
+						count--;
+					}
+				} else {
+					krk_push(tuple);
+				}
+				break;
+			}
 		}
 		if (!(vm.flags & KRK_HAS_EXCEPTION)) continue;
 _finishException: