Set

:::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. :::

Stores a value into the current collection with the specified key, overwriting the previous value associated with the key

public function set(
  Tk $k,
  Tv $v,
): this;

If the key is not present, an exception is thrown. If you want to add a value even if a key is not present, use add().

$coll->set($k,$v) is semantically equivalent to $coll[$k] = $v (except that set() returns the current collection).

It returns the current collection, meaning changes made to the current collection will be reflected in the returned collection.

Parameters

• Tk $k - The key to which we will set the value.
• Tv $v - The value to set.

Returns

• this - Returns itself.