HH\Lib\Keyset\map

This API is part of the Hack Standard Library, not HHVM itself.

Returns a new keyset where each value is the result of calling the given function on the original value

namespace HH\Lib\Keyset;

function map<Tv1, Tv2 as arraykey>(
    Traversable<Tv1> $traversable,
  (function(Tv1):Tv2) $value_func,
): keyset<Tv2>;

Parameters