WARP9

Atomic Updates

Yes, warp9 supports it. To do atomically change to several variable you should put those changes into lambda and pass the lambda to warp9.tx, it returns a function that do the specified atomic updates when it is invoked.

Details Knockout Reactive Coffee Warp9

JS

var alice = new warp9.Cell(10);
var bob = new warp9.Cell(15);
var history = new warp9.List();
var snapshot = warp9.do(function(){
    return JSON.stringify({
        Alice: alice.get() + "$",
        Bob: bob.get() + "$",
        sum: (alice.get() + bob.get()) + "$"
    });
});
snapshot.onChange(function(snapshot){
    history.add(snapshot.get());
});
var parcel = new warp9.Cell("2");

warp9.render(placeholder, ["div",
    ["div",
        ["div", {"class": "accounts-title"},
            ["div", ["b", "Alice's account"]],
            ["div", ["b", "Bob's account"]]],
        ["div", {"class": "accounts-value"},
            ["div", ["span", alice, "$"]],
            ["div", ["span", bob, "$"]]],
        ["div", {"class": "clear"}]],
    ["div", {"class": "transfer"},
        ["input-text", parcel],
        ["button", {"!click": warp9.tx(function(){
            alice.set(alice.get()-parseInt(parcel.get()));
            bob.set(bob.get()+parseInt(parcel.get()));
        })}, "Transfer from Alice to Bob"]],
    ["div", {"class": "history"},
        ["div", ["b", "Account history"]],
        ["div", {"class": "snapshots"}, history.lift(function(item){
            return ["div", item];
        })]]
]);