Function with 3 arguments: Return result after applying operator i.e. (5, 7, '+') = 35

Question

Hopefully my title explains it but I need a function that will take 3 arguments (two numbers and an operator [*, +, /, -]), then compute the result.

Something like this:

function evaluateExpression (firstNum, secondNum, operator) {
    ...
    return ...;
}

evaluateExpression (35, 7, '/'); // should return 5

Answer 1

Pseudocode:

evaluateExpression( first, second, op ) :

    if op == "+" :
         return first + second

    else if op == "*" :
         return first * second

    ... etc

    else :
         return error