arrayTransform

a.js

//Transforms array a into the value of b while maintaining the original reference of a. Useful for updating synced arrays
function arrayTransform(a,b){
    var old = a.slice();

    b.forEach(function(i){
        if(a.indexOf(i) === -1){
            a.push(i);
        }
    });

    old.forEach(function(i){
        if(b.indexOf(i) === -1){
            var k = a.indexOf(i);
            a.splice(k,1);
        }
    });

}