Requires the Hack Standard Library to be installed.
Facebook Engineer?

This function is available as Dict\from_keys() in Facebook's www repository.

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>;

Time complexity: O(n * f), where f is the complexity of $value_func Space complexity: O(n)



  • dict<Tk, Tv>