IsDefaultNamespace - Hhvm

:::info[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. :::

Tells whether namespaceURI is the default namespace

Hack

public function isDefaultNamespace(
  string $namespaceuri,
): bool;

Parameters

string $namespaceuri - The namespace URI to look for.

Returns

bool - - Return TRUE if namespaceURI is the default namespace, FALSE otherwise.