# ethereumjs-util
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A collection of utility functions for Ethereum. It can be used in Node.js and in the browser with [browserify](http://browserify.org/).
# INSTALL
`npm install ethereumjs-util`
# USAGE
```js
import assert from 'assert'
import { isValidChecksumAddress, unpadBuffer, BN } from 'ethereumjs-util'
assert.ok(isValidChecksumAddress('0x2F015C60E0be116B1f0CD534704Db9c92118FB6A'))
assert.ok(unpadBuffer(Buffer.from('000000006600', 'hex')).equals(Buffer.from('6600', 'hex')))
assert.ok(new BN('dead', 16).add(new BN('101010', 2)).eqn(57047))
```
# API
## Documentation
Read the [API docs](docs/).
### Modules
- [account](src/account.ts)
- Account class
- Private/public key and address-related functionality (creation, validation, conversion)
- [address](src/address.ts)
- Address class and type
- [bytes](src/bytes.ts)
- Byte-related helper and conversion functions
- [constants](src/constants.ts)
- Exposed constants
- e.g. `KECCAK256_NULL_S` for string representation of Keccak-256 hash of null
- [hash](src/hash.ts)
- Hash functions
- [object](src/object.ts)
- Helper function for creating a binary object (`DEPRECATED`)
- [signature](src/signature.ts)
- Signing, signature validation, conversion, recovery
- [types](src/types.ts)
- Helpful TypeScript types
- [internal](src/internal.ts)
- Internalized helper methods
- [externals](src/externals.ts)
- Re-exports of `BN`, `rlp`
### ethjs-util methods
The following methods are available by an internalized version of the [ethjs-util](https://github.com/ethjs/ethjs-util) package (`MIT` license), see [internal.ts](src/internal.ts). The original package is not maintained any more and the original functionality will be replaced by own implementations over time (starting with the `v7.1.3` release, October 2021).
- arrayContainsArray
- getBinarySize
- stripHexPrefix
- isHexPrefixed
- isHexString
- padToEven
- fromAscii
- fromUtf8
- toUtf8
- toAscii
- getKeys
They can be imported by name:
```js
import { stripHexPrefix } from 'ethereumjs-util'
```
### Re-Exports
`ethereumjs-util` re-exports the following commonly-used libraries:
- [BN.js](https://github.com/indutny/bn.js) (version `5.x`)
- [rlp](https://github.com/ethereumjs/rlp) (version `2.x`)
They can be imported by name:
```js
import { BN, rlp } from 'ethereumjs-util'
```
# EthereumJS
See our organizational [documentation](https://ethereumjs.readthedocs.io) for an introduction to `EthereumJS` as well as information on current standards and best practices.
If you want to join for work or do improvements on the libraries have a look at our [contribution guidelines](https://ethereumjs.readthedocs.io/en/latest/contributing.html).
# LICENSE
MPL-2.0
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