HH\Asio\vmk
Returns an Awaitable
of Vector
after a mapping operation has been
applied to each key and value in the provided KeyedTraversable
namespace HH\Asio;
function vmk<Tk, Tv, Tr>(
KeyedTraversable<Tk, Tv> $inputs,
(function(Tk, Tv): Awaitable<Tr>) $callable,
): Awaitable<Vector<Tr>>;
This function is similar to vm()
, but passes element keys to the callable
as well.
This function is similar to Vector::mapWithKey()
, but the mapping of the
keys and values is done using Awaitable
s.
This function is called vmk
because we are returning a v
ector and doing
a m
apping operation that includes k
eys.
$callable
must return an Awaitable
.
The values in the Vector
of the returned Awaitable
are not available
until you await
or join
the returned Awaitable
.
Parameters
KeyedTraversable<Tk,
Tv> $inputs
- TheKeyedTraversable
of keys and values to map.(function(Tk, Tv): Awaitable<Tr>) $callable
- The callable containing theAwaitable
operation to apply to$inputs
.
Returns
Awaitable<Vector<Tr>>
- AnAwaitable
ofVector
after the mapping operation has been applied to both the keys and values in$inputs
.
Examples
/**
* Query an arbitrary number of URLs in parallel
* returning them as a Vector of string responses.
*/
async function get_urls(\ConstVector<string> $urls): Awaitable<Vector<string>> {
// Await on curl requests in parallel and
// prepend the request ID index
return await \HH\Asio\vmk(
$urls,
async ($idx, $url) ==> {
$content = await \HH\Asio\curl_exec($url);
return $idx." => ".$content;
},
);
}
<<__EntryPoint>>
async function basic_usage_main(): Awaitable<void> {
$urls = ImmVector {
"http://example.com",
"http://example.net",
"http://example.org",
};
$pages = await get_urls($urls);
foreach ($pages as $page) {
echo \substr($page, 0, 20).' ... '.\substr($page, -8);
}
}
```.skipif
// Skip if we don't have an internet connection
if (!\get_headers("www.example.com")) {
print "skip";
}