Merge pull request #157 from Jason2605/feature/multiple_assignment

Multiple assignment

c/compiler.c

@@ -1202,18 +1202,21 @@ static void funDeclaration(Compiler *compiler) {
 }
 
 static void varDeclaration(Compiler *compiler) {
-    uint8_t global = parseVariable(compiler, "Expect variable name.");
+    do {
+        uint8_t global = parseVariable(compiler, "Expect variable name.");
 
-    if (match(compiler, TOKEN_EQUAL)) {
-        // Compile the initializer.
-        expression(compiler);
-    } else {
-        // Default to nil.
-        emitByte(compiler, OP_NIL);
-    }
-    consume(compiler, TOKEN_SEMICOLON, "Expect ';' after variable declaration.");
+        if (match(compiler, TOKEN_EQUAL)) {
+            // Compile the initializer.
+            expression(compiler);
+        } else {
+            // Default to nil.
+            emitByte(compiler, OP_NIL);
+        }
 
-    defineVariable(compiler, global);
+        defineVariable(compiler, global);
+    } while (match(compiler, TOKEN_COMMA));
+
+    consume(compiler, TOKEN_SEMICOLON, "Expect ';' after variable declaration.");
 }
 
 static void expressionStatement(Compiler *compiler) {

docs/docs/variables.md

@@ -60,3 +60,10 @@ E.g
 var someVariable = 10;
 someVariable = "Some text"; // Is perfectly valid
 ```
+
+You can also define multiple variables with a single statement.
+
+```js
+var a, b = 10, c = "hello!";
+print(a, b, c); // nil, 10, 'hello!'
+```

tests/variables/assignment.du

@@ -16,4 +16,15 @@ assert(test == 123);
 
 // Test assignment of declared var
 x = 100;
-assert(x == 100);
+assert(x == 100);
+
+// Test multiple variable assignment in a single statement
+
+var a, b = 10, c, d = "test", e = [1, 2], f = {"test": 10};
+
+assert(a == nil);
+assert(b == 10);
+assert(c == nil);
+assert(d == "test");
+assert(e == [1, 2]);
+assert(f == {"test": 10});