HH\Lib\Dict\from_keys
Returns a new dict where each value is the result of calling the given function on the corresponding key
namespace HH\Lib\Dict;
function from_keys<Tk as arraykey, Tv>(
Traversable<Tk> $keys,
(function(Tk): Tv) $value_func,
): dict<Tk, Tv>;
- To use an async function, see
Dict\from_key_async()
. - To create a dict from values, see
Dict\from_values()
. - To create a dict from key/value tuples, see
Dict\from_entries()
.
Time complexity: O(n * f), where f is the complexity of $value_func
Space complexity: O(n)
Parameters
Traversable<Tk>
$keys
(function(Tk): Tv) $value_func
Returns
dict<Tk, Tv>
Examples
$keys = vec[1, 2, 3, 4];
$dict = Dict\from_keys($keys, $x ==> $x + 1);
\print_r($dict);
$values = vec[1, 2, 3, 4];
$dict = Dict\from_keys($keys, $x ==> 5);
\print_r($dict);