[near-runtime-ts](../README.md) > ["collections/index"](../modules/_collections_index_.md) > [collections](../modules/_collections_index_.collections.md)

# Module: collections

Classes and functions for persistent collections on the blockchain.

## Index

### Classes

* [MapEntry](../classes/_collections_index_.collections.mapentry.md)

### Variables

* [_KEY_BACK_INDEX_SUFFIX](_collections_index_.collections.md#_key_back_index_suffix)
* [_KEY_ELEMENT_SUFFIX](_collections_index_.collections.md#_key_element_suffix)
* [_KEY_FRONT_INDEX_SUFFIX](_collections_index_.collections.md#_key_front_index_suffix)
* [_KEY_LENGTH_SUFFIX](_collections_index_.collections.md#_key_length_suffix)
* [_KEY_RATING_SUFFIX](_collections_index_.collections.md#_key_rating_suffix)
* [_RATING_OFFSET](_collections_index_.collections.md#_rating_offset)

---

## Variables

<a id="_key_back_index_suffix"></a>

### `<Const>` _KEY_BACK_INDEX_SUFFIX

**● _KEY_BACK_INDEX_SUFFIX**: *":back"* = ":back"

*Defined in [collections/index.ts:7](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L7)*

___
<a id="_key_element_suffix"></a>

### `<Const>` _KEY_ELEMENT_SUFFIX

**● _KEY_ELEMENT_SUFFIX**: *"::"* = "::"

*Defined in [collections/index.ts:8](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L8)*

___
<a id="_key_front_index_suffix"></a>

### `<Const>` _KEY_FRONT_INDEX_SUFFIX

**● _KEY_FRONT_INDEX_SUFFIX**: *":front"* = ":front"

*Defined in [collections/index.ts:6](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L6)*

___
<a id="_key_length_suffix"></a>

### `<Const>` _KEY_LENGTH_SUFFIX

**● _KEY_LENGTH_SUFFIX**: *":len"* = ":len"

*Defined in [collections/index.ts:5](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L5)*

___
<a id="_key_rating_suffix"></a>

### `<Const>` _KEY_RATING_SUFFIX

**● _KEY_RATING_SUFFIX**: *":r"* = ":r"

*Defined in [collections/index.ts:9](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L9)*

___
<a id="_rating_offset"></a>

### `<Const>` _RATING_OFFSET

**● _RATING_OFFSET**: *`u64`* = 2147483648

*Defined in [collections/index.ts:10](https://github.com/nearprotocol/near-runtime-ts/blob/6995971/assembly/collections/index.ts#L10)*

___