Check exactly one boolean option set

Question

Well, this is kind of hacky:

function b2n(boo) {
    return boo ? 1 : 0;
}

if(b2n(opt1) + b2n(opt2) + b2n(opt3) !== 1) {
    throw new Error(\"Exactly one o         


        

Answer 1

I think you are being too clever, what's wrong with:

var optionsSelected = 0;
if( opt1 ) optionsSelected++;
if( opt2 ) optionsSelected++;
if( opt3 ) optionsSelected++;

if( optionsSelected !== 1 ) {
    throw new Error("Exactly one option must be set");
}

Of course I can play the clever game too:

 if( opts.filter(Boolean).length !== 1 ) {
     throw new Error("Exactly one option must be set");
 }