Cas

:::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. :::

Compare and set

public function cas(
  int $cas,
  string $key,
  string $value,
  int $expiration = 0,
): Awaitable<void>;

Parameters

• int $cas - CAS token as returned by getRecord()
• string $key - Name of the key to store
• string $value - Datum to store
• int $expiration = 0

Returns

• Awaitable<void>