HH\Lib\Dict\filter

This API is part of the Hack Standard Library, not HHVM itself.
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This function is available as Dict\filter() in Facebook's www repository.

Returns a new dict containing only the values for which the given predicate returns true

Description

namespace HH\Lib\Dict;

function filter<Tk as arraykey, Tv>(
  KeyedTraversable<Tk, Tv> $traversable,
  ?(function(Tv):bool) $value_predicate = null,
): dict<Tk, Tv>;

The default predicate is casting the value to boolean.

Parameters