HH\Asio\mfk
Returns an Awaitable of Map after a filtering operation has been
applied to each key and value in the provided KeyedTraversable
namespace HH\Asio;
function mfk<Tk as arraykey, Tv>(
KeyedTraversable<Tk, Tv> $inputs,
(function(Tk, Tv): Awaitable<bool>) $callable,
): Awaitable<Map<Tk, Tv>>;
This function is similar to mf(), but passes element keys to the callable
as well.
This function is similar to Map::filterWithKey(), but the filtering of the
keys and values is done using Awaitables.
This function is called mfk because we are returning a map, doing a
a filtering operation that includes keys.
$callable must return an Awaitable of bool.
The keys and values in the Map of the returned Awaitable are not
available until you await or join the returned Awaitable.
Parameters
KeyedTraversable<Tk,Tv> $inputs- TheKeyedTraversableof keys and values to filter.(function(Tk, Tv): Awaitable<bool>) $callable- The callable containing theAwaitableoperation to apply to$inputs.
Returns
Awaitable<Map<Tk,Tv>>- AnAwaitableofMapafter the filtering operation has been applied to both the keys and values in$inputs.
Examples
enum COLOR: int {
RED = 1;
ORANGE = 2;
YELLOW = 3;
GREEN = 4;
BLUE = 5;
INDIGO = 6;
VIOLET = 7;
}
<<__EntryPoint>>
async function basic_usage_main(): Awaitable<void> {
$fruits = ImmMap {
'Apple' => COLOR::RED,
'Banana' => COLOR::YELLOW,
'Grape' => COLOR::GREEN,
'Orange' => COLOR::ORANGE,
'Pineapple' => COLOR::YELLOW,
'Tangerine' => COLOR::ORANGE,
};
// Similar to $times->filter(...)
// But awaits the awaitable result of the callback
// rather than using it directly
$not_self_named = await \HH\Asio\mfk(
$fruits,
// Exclude fruits who's name is the same as their color
async ($name, $color) ==> \strcasecmp($name, COLOR::getNames()[$color]),
);
foreach ($not_self_named as $fruit => $color) {
echo $fruit, 's are ', COLOR::getNames()[$color], "\n";
}
}