BinaryOperator(first, second)

Creates a BinaryOperation from two given arguments.

If an argument is not an expression, it will be wrapped in an appropriate literal.

  • A (positive) number will be encapsulated in a Number Literal,
  • A string will be encapsulated in a Variable Literal.

Source 

BinaryOperator(first, second) {
  this.first = _toExpression(first);
  this.second = _toExpression(second);
}