Backbone.Radio: What are the benefits of event commands and queries?

Question

Backbone.Radio seems to provide 2 new abstractions - commands and queries. They are pretty much identical to Backbone.Events, except that they can only have one subscriber. This is so, and if so, what advantage do they provide for events?

I plan to use Backbone.Events/Radio with React.js if this helps.

Answer 1

I didn't actually use Backbone.Radio, but I used Backbone.wreqr https://github.com/marionettejs/backbone.wreqr widely , which provides an almost identical command service.

In my use, the difference between events and commands:

To work with events, the sender and receiver of the event must exist and have a link to each other, and the receiver must be able to correctly handle the event. This can often be problematic in a completely asynchronous browser environment where different parts of the application work simultaneously.

Commands allow you to separate the sender and receiver. One object, say, View A, can simply send the update_user_details command.

My second Object View B sets up a command handler for 'update_user_details', which will change the user data on the screen.

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Answer 2

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