code: function parseArguments() {
    var args = [];
  
    expect('(');
  
    if (!match(')')) {
      while (index < length) {
        args.push(parseConditionalExpression());
        if (match(')')) {
          break;
        }
        expect(',');
      }
    }
  
    expect(')');
  
    return args;
  }
docs: 11.2 Left-Hand-Side Expressions