function isNonCommutativeOperatorWithShorthand(operator) {
	return ["+", "-", "/", "%", "<<", ">>", ">>>", "**"].includes(operator);
}
Checks whether an operator is not commutative and has an operator assignment
shorthand form.
@param {string} operator Operator to check.
@returns {boolean} True if the operator is not commutative and has
    a shorthand form.