Ts-rust NPM | npm.io

ts-rust

Typescript porting of Rust's Option and Result

Project Goal

Portaing all TypeScript implementable functions from Rust's Option and Result
Not snake_case but camelCase
Debug friendly
No external dependency

Pre-requirements

TypeScript target is ES6 or above

{
  "compilerOptions": {
    "target": "es6"
  }
}

Install

$ npm install --save ts-rust

Usage

import

import {RustOption as Option, RustResult as Result} from 'ts-rust'

types

const something:Option<number> = Option.Some(123);
const nothing:Option<number> = Option.None;

const okay:Result<number, string> = Result.Ok(222);
const error:Result<number, string> = Result.Err('failed');

Examples

import {RustOption as Option, RustResult as Result} from 'ts-rust'

let latestTemperature:Option<number> = Option.None;
const temperatureHistory:number[] = [];

function setTemperature(value:number){
    latestTemperature = Option.Some(value);
    temperatureHistory.push(value);
}

function printLatestTemperature(){
    latestTemperature.match({
        Some: (v)=>console.log('latest temperature = '+ v),
        None: ()=>console.log('no data in history')
    });
}

function findMinusValues(){
    const minusTemperatures = temperatureHistory.filter(v=>v<0);
    if(minusTemperatures.length === 0){
        return Result.Err('no minus value in history')
    }
    else{
        return Result.Ok(minusTemperatures);
    }
}

setTemperature(12);
setTemperature(-3);
setTemperature(5);

printLatestTemperature(); //value=567

const result = findMinusValues();
result.map(v=>console.log('Too cold! temperature = ' + v)); //Too cold! temperature = -3

Option

$ npm run example-option

example/option.ts

const something = Option.Some(123);
const nothing = Option.None;


console.log('Some.unwrap() = ', something.unwrap()); //123

console.log('Some.unwrapOr() = ', something.unwrapOr(456)); //123
console.log('None.unwrapOr() = ', nothing.unwrapOr(456)); //456

console.log('Some.isSome() = ', something.isSome()); //true
console.log('Some.isNone() = ', something.isNone()); //false

...

Result

$ npm run example-result

example/result.ts

const okay = Result.Ok(123);
const error = Result.Err('failed');


console.log('Ok.unwrap() = ', okay.unwrap()); //123

console.log('Ok.unwrapOr() = ', okay.unwrapOr(456)); //123
console.log('Err.unwrapOr() = ', error.unwrapOr(456)); //456

console.log('Ok.isOk() = ', okay.isOk()); //true
console.log('Ok.isErr() = ', okay.isErr()); //false