amp/docs/coroutines/helpers.md

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docs	Coroutine Helpers	/coroutines/helpers

Amp\Coroutine requires an already instantiated Generator to be passed to its constructor. Always calling a callable before passing the Generator to Amp\Coroutine is unnecessary boilerplate.

coroutine()

Returns a new function that wraps $callback in a promise/coroutine-aware function that automatically runs generators as coroutines. The returned function always returns a promise when invoked. Errors have to be handled by the callback caller or they will go unnoticed.

function coroutine(callable $callback): callable { ... }

Use this function to create a coroutine-aware callable for a promise-aware callback caller.

asyncCoroutine()

Same as coroutine() but doesn't return a Promise when the returned callback is called. Instead, promises are passed to Amp\Promise\rethrow() to handle errors automatically.

call()

function call(callable $callback, ...$args): Promise { ... }

Calls the given function, always returning a promise. If the function returns a Generator, it will be run as a coroutine. If the function throws, a failed promise will be returned.

call($callable, ...$args) is equivalent to coroutine($callable)(...$args).

asyncCall()

function asyncCall(callable $callback, ...$args) { ... }

Same as call(), but doesn't return the Promise. Promises are automatically passed to Amp\Promise\rethrow for error handling.