@toreda/types NPM

`@toreda/types`

Improve readability, reduce redundancy. Functional & Expressive Types used in Toreda packages.

@toreda/types
Contents
Object API - Resettable - Example - Clearable - Example - Stringable - Example
Functional Types - DeepRequired<T> - Primitive - Import - Use - Stringable - Import - Use
Expressive Types - BitMask - Import - Use
Install - Yarn - NPM
Legal - License - Copyright - Website

Object API

`Resettable`

Interface indicating implementer provides a reset method.

Example

import type {Resettable} from '@toreda/types';

class MyObj implements Resettable {
	public reset(): void {
		console.log('boop');
	}
}

const o = new MyObj();
o.reset();

`Clearable`

Interface indicating implementer provides a clear() method. Callers expect true to be returned when clear call is successful and false when it was not successful, or there was nothing to clear.

Example

import type {Clearable} from '@toreda/types';

class MyObj implements Clearable {
	public clear(): boolean {
		console.log('boop');

		return true;
	}
}

const o = new MyObj();
const result = o.clear();

`Stringable`

Interface indicating implementer provides a toString() method which returns the object contents as a string. Typically used for serialization although usage may vary.

Example

import type {Stringable} from '@toreda/types';

class MyObj implements Stringable {
	public a: string;
	public b: string;

	constructor() {
		this.a = 'aaaa';
		this.b = 'bbbb';
	}

	public toString(): string | null {
		const o = {
			a: this.a,
			b: this.b
		};

		let result: string | null = null;
		try {
			result =  JSON.stringify(o);
		} catch (e){
			if (e instanceof Error) {
				console.log(`toString exception: ${e.message}.`);
			}
		}

		return result;
	}
}

const o = new MyObj();
const result = o.clear();

Functional Types

Types & aliases provide shorthand to reduce code duplication and simplify statements.

`DeepRequired<T>`

Recursively require all properties on object & children.

`Primitive`

Implementer's type is any JavaScript primitive.

Import

import {Primitive} from '@toreda/types'

Use

const myValue: Primitive = null;

`Stringable`

Implementer's contents can be converted to a string by calling toString().

Import

import {Stringable} from '@toreda/types'

Use

export class MyClass implements Stringable {
	public toString(): string {
		return 'stringified_contents_here';
	}
}

Example

// Simple generic mapping. When used only once, exporting a type is overkill, but when used repeatedly
// using a common definition reduces chances for mistakes and reduces line lengths.
export type Data<T> = Record<string, T | T[] | null>;

Expressive Types

Express value intent & purpose with type definitions.

`BitMask`

Import

import {BitMask} from '@toreda/types'

Use

// Declare and initialize number while also expressing the value's purpose.
let mask: BitMask = 0x1;

// Becomes more clear when expecting values:
function useValue(mask: BitMask): void {
	...
}
// versus:
function useValue(mask: number): void {
	...
}

Example

// Expressive Type alias.
export type BigId = string;

// BigId is an expressive alias replacing the use of 'string' for id's type. It makes no
// functional difference, however id types often impose character and length limitations meaning
// the value cannot be an arbitrary string. BigId gives the caller context for what string values
// are actually valid & accepted.
function validateId(id: BigId): void {
	...
}