SuperMemo

A JavaScript/TypeScript implementation of the SuperMemo 2 (SM2) algorithm for spaced based repetition flashcards.

Hit the Star button if you love this project ⭐️

Explanation

type SuperMemoItem = {
  interval: number;
  repetition: number;
  efactor: number;
};

type SuperMemoGrade = 0 | 1 | 2 | 3 | 4 | 5;

supermemo(item: SuperMemoItem, grade: SuperMemoGrade): SuperMemoItem
  • item
    • repetition: the number of continous correct responses.
    • interval: inter-repetition interval after the repetitions (in days).
    • efactor: easiness factor reflecting the easiness of memorizing and retaining a given item in memory.
  • grade:
    • 5: perfect response.
    • 4: correct response after a hesitation.
    • 3: correct response recalled with serious difficulty.
    • 2: incorrect response; where the correct one seemed easy to recall.
    • 1: incorrect response; the correct one remembered.
    • 0: complete blackout.

Installation

For Webpack

npm install --save supermemo
import { supermemo, SuperMemoItem, SuperMemoGrade } from 'supermemo';

For Node

npm install --save supermemo
const supermemo = require('supermemo');

For Deno

import { supermemo, SuperMemoItem, SuperMemoGrade } from 'https://deno.land/x/supermemo/mod.ts';

Usage

let item: SuperMemoItem = {
  interval: 0,
  repetition: 0,
  efactor: 2.5,
};

console.log(item);

item = supermemo(item, 5);
console.log(item);

item = supermemo(item, 4);
console.log(item);

References