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

@spudly is on the right track, but it could be a little more compact:

if( [opt1,opt2,opt3].filter(function(x){return x}).length!==1 ) {
    throw new Error("Exactly one option must be set");
}

See ES5's filter method for more information.