var A = function() {
    var aDFD = $.Deferred();
    $.get('/api', {var:'foo'}, function(result){
        aDFD.resolve('data':result);
    });
    return aDFD.promise();
}

var B = function() {
    var bDFD = $.Deferred();
    $.get('/api', {var:'bar'}, function(result){
        bDFD.resolve('data':result);
    });
    return bDFD.promise();
}

$.when(A(), B()).then(function(a, b){
    alert("A() and B() both finished");
    console.log(a.data);
    console.log(b.data);
});