Javascript function(params) and function({ params }), one function two call types

Question

Is there any way I could write a function in order to call it in both ways like this?

I know how to write both params structures in the function but I would like to know how to validate both params structures in a single function.

functionToCall(1, 'value', true);

and

functionToCall({
    param1: 1,
    param2: 'value',
    param3: true
});

do you expect a different type for the first parameter than an object? — Nina Scholz, Dec 10 '19 at 21:28
Yes, [you could](https://stackoverflow.com/q/12694588/1048572), but no, you shouldn't. — Bergi, Dec 10 '19 at 21:28
@Bergi - your original answer doesn't contain the shouldn't part. Please elaborate. — Ori Drori, Dec 10 '19 at 21:33
@OriDrori It's confusing to have both structures here, doing the same thing. One should choose one and stick to it, not plan to provide both. — Bergi, Dec 10 '19 at 21:39

score 0 · Answer 1 · answered Dec 10 '19 at 21:30

You could check the first parameter, if it is an object and take a destruturing for the missing parameters.

This approach does not work if the first parameter is an object as a regular wanted type or if the type is any.

function functionToCall(param1, param2, param3) {
    if (param1 && typeof param1 === 'object') {
        ({ param1, param2, param3 } = param1);
    }
    console.log(param1, param2, param3);
}

functionToCall(1, 'value', true);
functionToCall({ param1: 1, param2: 'value', param3: true });

Ori Drori · Answer 2 · 2019-12-10T21:37:31.177

You can use rest params to get an array of parameters. If the length of the args array is 1, use object destructuring. If it's not 1 use array destructuring on the args array.

const functionToCall = (...args) => {
  let param1, param2, param3;
  if (args.length === 1) ({ param1, param2, param3 } = args[0]);
  else ([param1, param2, param3] = args);
  
  console.log(param1, param2, param3);
};

functionToCall(1, 'value', true);

functionToCall({
    param1: 1,
    param2: 'value',
    param3: true
});

score 0 · Answer 3 · answered Dec 10 '19 at 21:33

0

You can do like this for example

const functionToCall = () => {
  val [param1, param2, param3] = arguments.length == 1 
    ? Object.entries(arguments[0]).map(v => v[1]) 
    : arguments     
}

answered Dec 10 '19 at 21:33

Dmitry Reutov

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Javascript function(params) and function({ params }), one function two call types

3 Answers3