Array (or object) values intersection.

ObjectIntersect.js

// Exapmle var foo = intersect({foo: [1, 2, 5, 8], bar: {two: 2, tree: 3, four: 4, five: 5, six: 6}});

function intersect (arrList) { // Calculate intersection of multiple array or object values: //{{{

    var l = Object.keys(arrList).length; // Also accepts regular objects as input.
    var index = {};
    
    for (var i in arrList) {
        for (var j in arrList[i]) {
            var v = arrList[i][j];
            if (index[v] === undefined) index[v] = 0;
            index[v]++;
        };  
    };  
    
    var retv = [];
    for (var i in index) {
        if (index[i] == l) retv.push(i);
    };  
    
    return retv;
    
};//}}}