CODEWITHSUNDEEP
arraystypescriptecmascript-6variadic-functions
tengobash
tengobash

Reputation: 367

Force at least one argument for rest parameter

I searched for an answer for this but did not find an answer:
Is there a way to force at least one argument for a rest parameter?
In the code below all three calls to logArray are valid but I want the first one to fail.

function logArray(...elements: number[]) {
    elements.forEach(x => console.log(x));
}

logArray(); // should fail but works
logArray(1);
logArray(1,2);

Upvotes: 3

Views: 332

Answers (1)

DAXaholic
DAXaholic

Reputation: 35338

One possible solution could be just adding a regular parameter in front of the rest parameter and concatenating it back in the function body like so 

function logArray(e1: number ,...erest: number[]) {
    [e1, ...erest].forEach(x => console.log(x));        
}

Upvotes: 4

Related Questions