HH\Lib\C\first_async

This API is part of the Hack Standard Library, not HHVM itself.
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Returns the first element of the result of the given Awaitable, or null if the Traversable is empty

Description

namespace HH\Lib\C;

function first_async<T>(
  Awaitable<Traversable<T>> $awaitable,
): Awaitable<?T>;

For non-Awaitable Traversables, see C\first.

Parameters