memo/readme.md

In-memory caching/memoization utilities

---

Install

npm install --save @js/memo

Usage

import { memo } from '@js/memo';

function get_data_from_slow_source(name: string) : string {
	// ....
}

const get_data_cached = memo({
	func: get_data_from_slow_source,
	ttl: 30_000,
});

Custom cache key generation

import { memo } from '@js/memo';

interface SomeObject {
	id: string;
	foo: string;
	bar: number;
	baz: {
		qux: string;
	};
}

function get_data_from_slow_source(obj: SomeObject) : string {
	// ....
}

const get_data_cached = memo({
	func: get_data_from_slow_source,
	ttl: 30_000,

	// Pull just the `id` field from the first parameter to use
	// as the cache key
	key([ obj ]) {
		return obj.id;
	},
});

Simple functions with no params

import { memo_simple } from '@js/memo';

function get_data_from_slow_source() : string {
	// ....
}

const get_data_cached = memo_simple(30_000, get_data_from_slow_source);

Full async example

import { memo_async } from '@js/memo';

async function get_data_from_slow_source(name: string) : Promise<string> {
	// ....
}

const get_data_cached = memo_async({
	func: get_data_from_slow_source,
	ttl: 30_000,
	stale_ttl: 5_000,
	promise_ttl: 5_000,
});