https://github.com/alexeyraspopov/dgelong
A JavaScript Implementation of Useful First-class Citizens.
https://github.com/alexeyraspopov/dgelong
Last synced: 5 months ago
JSON representation
A JavaScript Implementation of Useful First-class Citizens.
- Host: GitHub
- URL: https://github.com/alexeyraspopov/dgelong
- Owner: alexeyraspopov
- License: mit
- Created: 2015-06-03T10:40:45.000Z (almost 10 years ago)
- Default Branch: master
- Last Pushed: 2017-05-08T10:57:59.000Z (almost 8 years ago)
- Last Synced: 2024-12-01T03:33:58.768Z (5 months ago)
- Language: JavaScript
- Homepage: http://dgelong.js.org
- Size: 117 KB
- Stars: 13
- Watchers: 3
- Forks: 1
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# Dgelong
Set of useful first-class structures which allow you to get rid of your developer's pain.
* **Flatten** by default.
* **Minimal API sufrace area**.
* **Immutable**.
* **Lazy evaluation**.
* **Full interoperability** between all structures and JavaScript natives.
## Install
npm install dgelong
## Motivation
I don't want make another implementation that requires Ph.D in Math. The usage of monads should be as simple as functional composition `f(g(a))`. API should be close to native. So if we're talking about data structures, they should be produced in the same way as natives: by calling constructor function with or without `new` operator (I prefer the second approach).
## Usage
```javascript
import Dgelong from 'dgelong';
```
Or just use something specific, for example:
```javascript
import { Option, Either } from 'dgelong';
```
## Option
```javascript
import { Just, Nothing } from 'dgelong';
function square(n) {
return n * n;
}
function isEven(n) {
return n % 2 ? Nothing() : Just(n);
}
new Just(5)
.map(square) // returns Just(25)
.map(isEven) // returns Nothing()
.map(alert); // won't be executed
```
## Either
```javascript
import { Success, Failure } from 'dgelong/either';
function validateUserPassword(password) {
if (password.length < 10) return Failure('Password is too short');
if (!/[0-9]/g.test(password)) return Failure('Password should contain numbers');
return Success(password);
}
validateUserPassword('boo')
.map(savePassword, showError);
```