Memd

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• Memoize, debounce, throttle and queue methods
• Cache Handler
• Persistence: (File, LocalStorage, Custom)
• NodeJS/Browser

import { deco } from 'memd';

class Foo {
    @deco.memoize()
    someMethod () {}

    @deco.memoize()
    get someProp () {}

    @deco.debounce()
    bar () {}

    @deco.throttle()
    qux () {}

    @deco.queue()
    async dex () {}
}

Cache

import { Cache } from 'memd'

interface ICacheOpts {
    maxAge?: number
    monitors?: ICacheChangeEventMonitor[]
    keyResolver?: (...args) => string
}
interface ICacheChangeEventMonitor {
    on (event: 'change', fn: Function)
    off (event: 'change', fn: Function)
}

const cache = new Cache(<ICacheOpts> { maxAge: 60 });

.get (key: string): T
.set (key: string, val: T): T
.clear (key?: string)
.destroy ()

memoize

interface IMemoizeOpts {
    // Per default method or getter returns are cached for all instances of a class.
    // Use `perInstance` to cache per instance: this could be useful when the method reads `this.` values.
    perInstance?: boolean

    // When a promise is memoized, and gets rejected. Clear also the cache, so that
    // the next time it wont hit the cache and is reavaluated.
    clearOnReject?: boolean
}
.memoize(opts?: ICacheOpts & IMemoizeOpts)

debounce

When ms is 0 or undefined then requestAnimationFrame or setImmediate is used.

.debounce(ms: number = 0)

throttle

.throttle(ms: number, shouldCallLater?: boolean)

queued

Calls method only when the previous promise is resolved. Use trimQueue: true to ensure the queue consists of max 1 listener.

.queued(opts: { trimQueue?: boolean, timeout?: number, throttle?: number })

Transport and Store for Cache/Memoize

Transport

Persist all cached data to the backed store, to be able to restore on app restarts

(NodeJS) Files

import memd from 'memd'
const fs = new memd.FsTransport({ path: './lorem.json' });
class Foo {

    @memd.deco.memoize({ transport: fs })
    foo (bar) {
        // do smth
    }
}

(Browser) localStorage

import memd from 'memd'

const storage = new memd.LocalStorageTransport({ key: 'foo' });
class Foo {

    @memd.deco.memoize({ transport: storage })
    foo (bar) {
        // do smth
    }
}

Store

Read and Save single values from store

import memd from 'memd'

const store = {
    getAsync (key: string, ...args) {
        // get cached value if any
        return {
            value: 'bar'
        }
    },
    saveAsync (key: string, entry: { value: any, timestamp: number }) {
        // save cached value
    }
}
class Foo {

    @memd.deco.memoize({ store })
    foo (bar) {
        // do smth
    }
}

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Atma.js Project