ts-utls is a small TypeScript library where I put all the useful stuff I regularly need in my projects.
Feel free to use it at your discretion with the apppropriate credit mentions.
NB: I've developed the same kind of libraries for both Go and Python.
npm i ts-utlsThis library contains the following functions:
- For arrays:
chunk: split an array into chunks of a maximum size;flatten: transform an array of arrays of items to an array of items;groupBy: group an array of items by some item's field;range: return a list of integers;
- For bits and buffers:
buffer2BytesString: transform a byte array to its string representation of byte(s);int2Buffer: convert an integer to its byte array equivalent;splitBuffer: split a byte array using a passed byte array;stringBytes2Buffer: transform a string representing one or more bytes to a byte array;
- For JSON:
ConvertJSON.toClass: allows casting a JSON string to the targeted class instance;
- For numbers:
euclideanDivision: compute the euclidean division of two integers, returning the quotient and the remainder;
- For strings:
capitalize: capitalize the first letter of a sentence;fromHexandtoHex: transform hexadecimal string representation to byte array, and vice-versa;hashCode: compute the equivalent of Java's hashCode;reverse: reverse the order of characters;shuffle: randomly shuffle the characters;splitCamelCaseWords: put a space between each "word" found in a camel-case string;xor: apply the XOR logical function to two strings in the sense that each charCode is xored;
- For time:
currentTimestampMillis: return the current Unix timestamp in milliseconds;sleep: hold the current thread for a while;toMySQLDateOrEmpty: transform any date string to a MySQL-compatible date for SQL statement.
It also contains an extremely simplified version of Either, List and Maybe monads.
These latter implementations are heavily inspired by the monet library which I had to decouple in my work due to incompatibilities with TypeScript versions higher than 4.7, hence the creation of these monads.
However, they probably should still be challenged.
eg.
import { buffer2BytesString, capitalize, chunk, ConvertJSON, currentTimestampMillis, Either, euclideanDivision, flatten, fromHex, groupBy, hashCode, int2Buffer, List, Maybe, None, range, reverse, shuffle, sleep, Some, splitCamelCaseWords, splitBuffer, stringBytes2Buffer, Right, toHex, toMySQLDateOrEmpty, xor } from 'ts-utls' // For arrays const arr = [1, 2, 3, 4, 5] const chunked = chunk(arr, 2) // [[1, 2], [3, 4], [5]] console.log(chunked) const arrs = [[1, 2], [3, 4], [5]] const flattened = flatten(arrs) // [1, 2, 3, 4, 5] console.log(flattened) const arr = [{ field1: '1', field2: 1 }, { field1: '1', field2: 2 }, { field1: '3', field2: 3 }] const grouped = groupBy(arr, 'field1') console.assert(grouped['1'].length === 2) const firstFive = range(0, 5) // [0, 1, 2, 3, 4] console.log(firstFive) const evenBefore10 = range(0, 10, 2) // [0, 2, 4, 5, 6, 8] console.log(evenBefore10) // For bits and buffers const buf0 = Buffer.from([0, 1, 128, 2, 3]) const delimiter = Buffer.from([128]) const splitsWithout = splitBuffer(buf0, delimiter, false) // [[0, 1], [2, 3]] console.log(splitsWithout) const splitsWith = splitBuffer(buf0, delimiter, true) // [[0, 1], [128], [2, 3]] console.log(splitsWith) const buf1 = int2Buffer(1) console.assert(buf1[0] === 1) const str = '11011010' const buf2 = stringBytes2Buffer(str) console.assert(buf1[0] === 218) const str2 = buffer2BytesString(buf2) console.assert(str === str2) // For JSON const myClass = ConvertJSON(jsonStr).toClass(MyClass) assert(myClass instanceof MyClass) // For numbers const n = 15, d = 2 const [q, r] = euclideanDivision(n, d) console.assert(q === 7 && r === 1) // For strings const phrase = capitalize('my sentence is capitalized') console.assert(phrase === 'My sentence is capitalized') const h = hashCode('Hello') console.assert(h === 69609650) const hexStrings = ['ff'] const buffers = hexStrings.map(fromHex) const strings = buffers.map(toHex) console.assert(hexStrings[0] === strings[0]) const toReverse = 'abcd' const reversed = reverse(toReverse) console.assert(reversed === 'dcba') const str = 'abcd' const shuffled = shuffle(str) console.assert(str.length === shuffled.length) console.assert(str !== shuffled) const sentence = splitCamelCaseWords('myCamelCase') console.assert(sentence === 'my Camel Case') const a = 'a' const b = 'b' const xored = xor(a, b) console.assert(xored === '\u0003') // For time const ts = currentTimestampMillis() await sleep(100) console.assert(currentTimestampMillis() > ts + 100) const date = 'Fri Apr 8 2022 01:00:00 GMT+0200' const mysqlDatetime = toMySQLDateOrEmpty(date, true) console.assert(mysqlDatetime === '2022-04-08 01:00:00') // Either const eitherString = Either('string', true) console.assert(eitherString.isRight()) console.assert(eitherString.right() === 'string') const rightString = Right('right') console.assert(rightString.equals(eitherString)) // List const listString = List.fromArray(['a', 'b', 'c']) console.assert(!listString.isNil) console.assert(listString.head() === 'a') console.assert(listString.contains('b')) const filteredList = listString.filter(_ => _ !== 'a') console.assert(filteredList.toArray().equals(['b', 'c'])) // Maybe const maybeString: Maybe<string> = Some('string') console.assert(maybeString.isSome() && !maybeString.isNone() && maybeString.some() === 'string' && maybeString.getOrElse('nothing') === 'string') const nothing = None<string>() console.assert(nothing.isNone() && !nothing.isSome(), nothing.getOrElse('something') === 'something') const leftString = nothing.toEither('string') console.assert(leftString.isLeft() && leftString.left() === 'string')Please let me know if you have more optimized implementations of any of my stuff.
To run the tests, you would need to install live-server:
npm i -g live-serverNB: Tests use port 10005, beware if any other process is running on that port as such a conflict may disable them.
This library is distributed under a MIT license.
See the LICENSE file.
© 2020-2025 Cyril Dever. All rights reserved.