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Previous versions of Ember Concurrency recommended decorators-based APIs for declaring tasks, but these APIs are no longer recommended due to decorators not playing nicely with TypeScript-based APIs.
If you would like to see the older APIs, please check out the old docs site.
See this link.
In general, yes, but they're not officially supported or tested on, so your
mileage may vary.
The ES6 Generator Function syntax
that ember-concurrency relies on can be automatically transpiled using Babel
and regenerator. You may
need to experiment with your config/targets.js
and/or
ember-cli-babel settings to include the regenerator runtime and proper
transpilation for your needs.
ember-concurrency v2.0.0 uses WeakMap
for implementing decorators
and encapsulated tasks, so certain older browsers may require polyfills to use
these features.
Encapsulated tasks also use Proxy
, which may not be polyfillable, so this
feature may not be available.
Async functions are just syntax sugar for Promises. Promises aren't cancelable, and as of November 2020, there is no active TC39 specification under development for adding cancelation to promises. Tasks, in contrast, are cancelable.
The design of Promises is such that once a Promise has been created, it's not possible to externally reach in and resolve/reject a Promise. This constraint encourages a clear, unidirectional, structured architecture for building asynchronous chains of logic.
Like Promises, the return/reject value of an EC Task cannot be externally
set / overridden; in other words, once a Task has been performed, there's
no way to externally force it to return/reject early, with the exception of
cancelation. When you .cancel()
a task instance, the task
will "return" from wherever it is currently paused (e.g. at a await
).
Presently, there is no API to "delay" the cancelation of a Task once a cancel
has been requested, but this functionality might be added to future APIs.
.dispose()
(though this approach is frowned up in favor
of explicitly specifying when an observable should terminate -- e.g. via takeUntil()
).
Tasks can be canceled implicitly (via 1. host object destruction, 2. the
restartable
task modifier) or explicitly (via .cancel() / .cancelAll()
), though,
like Observables, the implicit approach is preferable.
.set()
values on the object the task lives on so that those
values can be easily displayed in the template. Tasks also expose the value / error
returned from the task function (see Derived State),
which are preferable to .set()
s where possible.
.isIdle / .isRunning / .numRunning
) and 3)
it's often easier to model domain state as bindable values rather than
discrete events.
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