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@DmitryBaranovskiy
Last active August 29, 2015 14:03
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Events…
// This gist is based on eve (https://github.com/adobe-webplatform/eve), but really any event based API will do
// Idea is to recreate backbone-like model, but on events only
// Model here is a hash-map, but it shouldn’t be. You could implement any structure this way.
function model(id) {
var modelid = ["model", id],
name = function () {
return modelid.concat.apply(modelid, arguments);
};
(function init() {
var model = {};
eve.on(name("set"), function (key, value) {
var old = {};
if (typeof key != "object") {
var attr = {};
attr[key] = value;
key = attr;
}
for (var k in key) {
old[k] = model[k];
model[k] = key[k];
eve(name("change", k), null, k, key[k], old[k]);
}
eve(name("update"), null, key, old);
});
eve.on(name("unset"), function (key) {
var old = model[key];
delete model[key];
eve(name("deleted"), null, key);
eve(name("update"));
});
eve.on(name("json"), function () {
this(JSON.stringify(model));
});
eve.on(name("get"), function (key) {
this(model[key]);
});
eve.on(name("has"), function (key) {
this(key in model);
});
eve.on(name("death"), function () {
eve.off(modelid);
});
}());
// the following part is optional.
// If id is known we could communicate with the model via events only
return {
id: function () {
return id;
},
"set": function (key, value) {
eve(name("set"), null, key, value);
},
"get": function (key) {
var res;
eve(name("get", key), function (value) {
res = value;
}, key);
return res;
},
has: function (key) {
var res;
eve(name("has"), function (value) {
res = value;
}, key);
return res;
},
unset: function (key) {
eve(name("unset"), null, key);
},
toJSON: function () {
var res;
eve(name("json"), function (value) {
res = value;
});
return res;
},
die: function () {
eve(name("death"));
},
// as I mentioned, I don’t like these methods, but for the sake of it…
listenTo: function (other, event, callback) {
var id = other.id(),
eventName = ["model", id].concat(event);
eve.on(eventName, callback);
eve.once(name("stopListening", id), function () {
eve.off(eventName, callback);
});
},
stopListening: function (other) {
eve(["stopListening", other ? other.id() : "*"]);
}
};
}
eve.on("*", function () {
console.debug(eve.nt());
});
var m1 = model(1),
m2 = model(2);
m1.set({a: 1, b: 2});
m1.die();
m2.set({a: m1.get("a"), b: m1.get("b")});
m2.unset("b");
console.log(m1.toJSON());
console.log(m2.toJSON());
@apsavin
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apsavin commented Jul 8, 2014

@DmitryBaranovskiy what do you want to do this? I don't get it, why do you need to recreate Backbone.Model api using events?

@apsavin
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apsavin commented Jul 8, 2014

The main prop is possibility to communicate with the model using events only (if id is known)?

@DmitryBaranovskiy
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My original question was, “What do you think of API like this?”. Like 100% event based. To show the API I created purely hypothetical example. “Why?” is irrelevant. What pros and cons do you see?

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