ConstCollection

:::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. :::

The base interface implemented for a collection type so that base information such as count and its items are available

Every concrete class indirectly implements this interface.

Guides

• Introduction
• Interfaces

Interface Synopsis

interface ConstCollection implements Countable, IPureStringishObject {...}

Public Methods

• ->count(): int
  Get the number of items in the collection

• ->isEmpty(): bool
  Is the collection empty?

• ->items(): HH\Iterable<Te>
  Get access to the items in the collection

• ->toDArray(): darray

• ->toVArray(): varray

Public Methods (IPureStringishObject)

• ->__toString(): string