Chapter 24.5

1 files changed, 25 insertions, 2 deletions

diff --git a/clox/src/compiler.c b/clox/src/compiler.c
index bd835f2..ea40d7e 100644
--- a/clox/src/compiler.c
+++ b/clox/src/compiler.c
@@ -143,7 +143,10 @@ static int emitJump(uint8_t instruction) {
   return currentChunk()->count - 2;
 }
 
-static void emitReturn() { emitByte(OP_RETURN); }
+static void emitReturn() {
+  emitByte(OP_NIL);
+  emitByte(OP_RETURN);
+}
 
 static uint8_t makeConstant(Value value) {
   int constant = addConstant(currentChunk(), value);
@@ -269,6 +272,26 @@ static void binary(bool canAssign) {
   }
 }
 
+static uint8_t argumentList() {
+  uint8_t argCount = 0;
+  if (!check(TOKEN_RIGHT_PAREN)) {
+    do {
+      expression();
+      if (argCount == 255) {
+        error("Can't have more than 255 arguments.");
+      }
+      argCount++;
+    } while (match(TOKEN_COMMA));
+  }
+  consume(TOKEN_RIGHT_PAREN, "Expect ')' after arguments.");
+  return argCount;
+}
+
+static void call(bool canAssign) {
+  uint8_t argCount = argumentList();
+  emitBytes(OP_CALL, argCount);
+}
+
 static void literal(bool canAssign) {
   switch (parser.previous.type) {
   case TOKEN_FALSE:
@@ -571,7 +594,7 @@ static void grouping(bool canAssign) {
 }
 
 ParseRule rules[] = {
-    [TOKEN_LEFT_PAREN] = {grouping, NULL, PREC_NONE},
+    [TOKEN_LEFT_PAREN] = {grouping, call, PREC_CALL},
     [TOKEN_RIGHT_PAREN] = {NULL, NULL, PREC_NONE},
     [TOKEN_LEFT_BRACE] = {NULL, NULL, PREC_NONE},
     [TOKEN_RIGHT_BRACE] = {NULL, NULL, PREC_NONE},