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filter_nulls

Note

This is a point-in-time snapshot of the API documentation from January 2026. Going forward, we will not be maintaining a public copy of these references, and recommend users to refer to the built-in signature helpers available in the Hack LSP instead for complete and up-to-date information.

Given a KeyedTraversable with nullable values, returns a new dict with null values removed

namespace HH\Lib\Dict;

function filter_nulls<Tk as arraykey, Tv>(
  KeyedTraversable<Tk, ?Tv> $traversable,
): dict<Tk, Tv>;

Time complexity: O(n) Space complexity: O(n)

Parameters​

Returns​

  • dict<Tk, Tv>