# hash-base [](https://www.npmjs.org/package/hash-base) [](https://travis-ci.org/crypto-browserify/hash-base) [](https://david-dm.org/crypto-browserify/hash-base#info=dependencies) [](https://github.com/feross/standard) Abstract base class to inherit from if you want to create streams implementing the same API as node crypto [Hash][1] (for [Cipher][2] / [Decipher][3] check [crypto-browserify/cipher-base][4]). ## Example ```js const HashBase = require('hash-base') const inherits = require('inherits') // our hash function is XOR sum of all bytes function MyHash () { HashBase.call(this, 1) // in bytes this._sum = 0x00 } inherits(MyHash, HashBase) MyHash.prototype._update = function () { for (let i = 0; i < this._block.length; ++i) this._sum ^= this._block[i] } MyHash.prototype._digest = function () { return this._sum } const data = Buffer.from([ 0x00, 0x42, 0x01 ]) const hash = new MyHash().update(data).digest() console.log(hash) // => 67 ``` You also can check [source code](index.js) or [crypto-browserify/md5.js][5] ## LICENSE MIT [1]: https://nodejs.org/api/crypto.html#crypto_class_hash [2]: https://nodejs.org/api/crypto.html#crypto_class_cipher [3]: https://nodejs.org/api/crypto.html#crypto_class_decipher [4]: https://github.com/crypto-browserify/cipher-base [5]: https://github.com/crypto-browserify/md5.js