Javascript: Function - Best practice to return error message of invalid parameter

Question

I have this simple function as an example and essentially if the parameter are the wrong type, I want it to return an error which can be read in the browser console that will display in the browsers set language. Instead of using console.error which requires me to enter a custom error, how will I go about this so the error message will explain the parameter types are not valid and in the language set by the browser?

function myFunction(a, b) {
    if (typeof(a) !== 'number' || typeof(b) !== 'number') {
        console.error('Parameter error')
        return null;
    }

    return a + b;
}

You'd have to translate that text into all different languages. — Jonas Wilms, Jul 21 '20 at 22:46

score 3 · Answer 1 · answered Jul 21 '20 at 22:48

3

Something like this is what you're looking for. Though, I don't know if the error message will be translated without you having to do additional work.

 function myFunction(a, b) {
     if (typeof(a) !== 'number' || typeof(b) !== 'number') {
         throw new TypeError();
     }
    
     return a + b;
  }

answered Jul 21 '20 at 22:48

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Do you need the "new" before TypeError()? – bhutto54 Jul 21 '20 at 22:58
1

@bhutto54 https://stackoverflow.com/questions/13294658/throw-errormsg-vs-throw-new-errormsg – 23k Jul 22 '20 at 00:11

Javascript: Function - Best practice to return error message of invalid parameter

1 Answers1