# orderedmap

> Persistent ordered mapping from strings

Latest version **2.1.1** (published 2023-05-17) · MIT license · 0 weekly downloads

## Install

```sh
npm install orderedmap
pnpm add orderedmap
yarn add orderedmap
bun add orderedmap
```

## Health

**Score 35/100 (D)** — status: abandoned.

Positive: has types; esm support; no vulnerabilities.

Warnings: low downloads.

Negative: abandoned.

## Facts

| | |
|---|---|
| Version | 2.1.1 |
| Published | 2023-05-17 |
| First published | 2016-12-23 |
| Weekly downloads | 0 |
| License | MIT |
| TypeScript types | bundled |
| Module format | ESM + CommonJS |
| Dependencies | 0 |
| Unpacked size | 14.5 KB |
| Known vulnerabilities | 0 |
| Install scripts | no |
| GitHub stars | 45 |
| Author | Marijn Haverbeke |
| Maintainers | marijn |
| Keywords | persistent, map |

## Links

- npm: https://www.npmjs.com/package/orderedmap
- Repository: https://github.com/marijnh/orderedmap
- Homepage: https://github.com/marijnh/orderedmap#readme
- Issues: https://github.com/marijnh/orderedmap/issues
- npm.io page: https://npm.io/package/orderedmap

## Recent versions

- 2.1.1 (latest) — 2023-05-17
- 2.1.0 — 2022-09-26
- 2.0.0 — 2022-06-15
- 1.1.8 — 2022-06-01
- 1.1.7 — 2022-05-14
- 1.1.6 — 2022-05-13
- 1.1.5 — 2022-02-22
- 1.1.4 — 2022-02-21
- 1.1.3 — 2022-02-19
- 1.1.2 — 2022-02-18
- 1.1.1 — 2020-01-22
- 1.1.0 — 2019-11-07
- 1.0.0 — 2016-12-23

## README

# OrderedMap

Persistent data structure representing an ordered mapping from strings
to values, with some convenient update methods.

This is not an efficient data structure for large maps, just a minimal
helper for cleanly creating and managing small maps in a way that
makes their key order explicit and easy to think about.

License: MIT

## Reference

The exported value from this module is the class `OrderedMap`,
instances of which represent a mapping from strings to arbitrary
values.

**`OrderedMap.from`**`(value: ?Object | OrderedMap) → OrderedMap`  
Return a map with the given content. If null, create an empty map. If
given an ordered map, return that map itself. If given an object,
create a map from the object's properties.

### Methods

Instances of `OrderedMap` have the following methods and properties:

**`get`**`(key: string) → ?any`  
Retrieve the value stored under `key`, or return undefined when
no such key exists.

**`update`**`(key: string, value: any, newKey: ?string) → OrderedMap`  
Create a new map by replacing the value of `key` with a new
value, or adding a binding to the end of the map. If `newKey` is
given, the key of the binding will be replaced with that key.

**`remove`**`(key: string) → OrderedMap`  
Return a map with the given key removed, if it existed.

**`addToStart`**`(key: string, value: any) → OrderedMap`  
Add a new key to the start of the map.

**`addToEnd`**`(key: string, value: any) → OrderedMap`  
Add a new key to the end of the map.

**`addBefore`**`(place: string, key: value: string, value: any) → OrderedMap`  
Add a key after the given key. If `place` is not found, the new
key is added to the end.

**`forEach`**`(f: (key: string, value: any))`  
Call the given function for each key/value pair in the map, in
order.

**`prepend`**`(map: Object | OrderedMap) → OrderedMap`  
Create a new map by prepending the keys in this map that don't
appear in `map` before the keys in `map`.

**`append`**`(map: Object | OrderedMap) → OrderedMap`  
Create a new map by appending the keys in this map that don't
appear in `map` after the keys in `map`.

**`subtract`**`(map: Object | OrderedMap) → OrderedMap`  
Create a map containing all the keys in this map that don't
appear in `map`.

**`toObject`**`() -> Object`
Return an object that has the same key/value pairs as the `map`.

**`size`**`: number`  
The amount of keys in this map.

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_Source: https://npm.io/package/orderedmap · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._