dirkluijk/typescript-essentials

Must-have utility types and functions for TypeScript

Typescript Essentials

Must-have utility types and functions for TypeScript

Overview

This is a small util library which contains several types and functions that may be useful in your TypeScript project.

Getting started 🌩

npm

npm install typescript-essentials

yarn

yarn add typescript-essentials

Contents

Predicates & type-guards

Useful to compose simple predicates, or to narrow types in arrays or other data structures.

• Predicate and TypeGuard interfaces
• not() function to negate predicates
• matchesDiscriminator() function that returns a type guard
• isNull() type guard
• isUndefined() type guard
• isNullOrUndefined() type guard
• isNotNull() type guard
• isNotUndefined() type guard
• isNotNullOrUndefined() type guard

Generics

• DiscriminatedUnion to narrow a union type using a discriminator field
• Narrowable to identify a type that can be narrowed
• Subtract to subtract types from one another
• WithOptional to make certain properties optional

Array utils

• uniqueValues()
• exclude()
• partition()

Object utils

• omit()

Ordered

• Ordered<T> interface
• compareByOrder() comparator function

"Track by" functions for Angular

• trackByIndex
• trackById
• trackByValue
• createTrackByFn

Contributors ✨

Thanks goes to these wonderful people (emoji key):

Dirk Luijk 💻 📖

Daan Scheerens 🤔

This project follows the all-contributors specification. Contributions of any kind welcome!