HH\Asio\mfw
Returns an Awaitable
of Map
of ResultOrExceptionWrapper
after a
filtering operation has been applied to each value in the provided
KeyedTraversable
namespace HH\Asio;
function mfw<Tk as arraykey, T>(
KeyedTraversable<Tk, T> $inputs,
(function(T): Awaitable<bool>) $callable,
): Awaitable<Map<Tk, ResultOrExceptionWrapper<T>>>;
This function is similar to mf()
, except the Map
in the returned
Awaitable
contains values of ResultOrExceptionWrapper
instead of raw
values.
This function is similar to Map::filter()
, but the filtering of the values
is done using Awaitable
s.
This function is called mfw
because we are returning a m
ap, doing a
f
iltering operation and each value member in the Map
is w
rapped by a
ResultOrExceptionWrapper
.
$callable
must return an Awaitable
of bool
.
The ResultOrExceptionWrapper
s in the Map
of the returned Awaitable
are not available until you await
or join
the returned Awaitable
.
Parameters
KeyedTraversable<Tk,
T> $inputs
- TheKeyedTraversable
of values to fitler.(function(T): Awaitable<bool>) $callable
- The callable containing theAwaitable
operation to apply to$inputs
.
Returns
Awaitable<Map<Tk,
ResultOrExceptionWrapper<T>>>
- AnAwaitable
ofMap
of key/ResultOrExceptionWrapper
pairs after the filterin operation has been applied to the values in$inputs
.
Examples
<<__EntryPoint>>
async function basic_usage_main(): Awaitable<void> {
// Return all non-negative odd numbers
// Positive evens filtered out,
// Negatives and zero cause exception
$odds = await \HH\Asio\mfw(
Map {
'-one' => -1,
'zero' => 0,
'one' => 1,
'two' => 2,
'three' => 3,
'four' => 4,
},
async ($val) ==> {
if ($val <= 0) {
throw new \Exception("$val is non-positive");
} else {
return ($val % 2) == 1;
}
},
);
foreach ($odds as $num => $result) {
if ($result->isSucceeded()) {
echo "$num Success: ";
\var_dump($result->getResult());
} else {
echo "$num Failed: ";
\var_dump($result->getException()->getMessage());
}
}
}