Installation

# npm
npm install plain-store
# yarn
yarn add plain-store

Usage

using with bundler or es module

import { createStore, isDeepEqual, deepFreeze } from 'plain-store';

const initialState = {
  count: 0
};

const store = createStore(initialState);
store.setStore({ count: 1 });

function Counter() {
  const { count } = store.useStore();
  // derive a new value from the store value
  const doubled = store.useSelector((state) => state.count * 2);
  return (
    <div>
      <div>count: {count}</div>
      <div>doubled: {doubled}</div>
      <button onClick={() => store.setStore((prev) => ({ count: 1 + prev.count }))}>Increment</button>
    </div>
  );
}

store.getStore(); // { count: 1 }
store.setStore((prev) => ({ count: 2 + prev.count })); // { count: 3 }, will trigger Counter re-render

using with script tag

<!-- include react -->
<script src="https://cdn.jsdelivr.net/npm/react/umd/react.production.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/plain-store/dist/index.iife.js"></script>
<script>
  const { createStore, isDeepEqual, deepFreeze } = PlainStore;
  const store = createStore({ count: 0 }, {
    onChange: (value) => {
      console.log('store value changed', value);
    }
  });
  store.setStore({ count: 1 });
</script>

API

createStore(initialState, options?)

Create a store with the initial state.

import { createStore } from 'plain-store';

interface ICreateStoreOptions<T> {
  /**
   * listen to the store value changes
   */
  onChange?: (value: Readonly<T>) => void;
  /**
   * custom comparator for store value changes, default to `isDeepEqual`
   * * use it when the default comparator is not working as expected
   * * `isDeepEqual` works for most cases, but it's not perfect, you can provide a custom comparator to handle the edge cases or performance issues.
   */
  comparator?: (a: any, b: any) => boolean;
}

interface ISetStoreOptions {
  /**
   * only update the partial value of the store,
   * * the new value will be merged with the old value
   */
  partial?: boolean;
}

type ISetStoreOptionsType = boolean | ISetStoreOptions

interface IStore<T> {
  // Get the current state of the store, none reactive, could be used anywhere.
  getStore: () => Readonly<T>;
  // Set the state of the store, could be used anywhere, callback could be async.
  // * return a promise if the params is async function
  // * use getStore() to get the latest state of the store when using async function
  // * use partial option to update the partial value of the store
  setStore(newValue: T | ((prev: T) => (T | Promise<T>)), cfg?: ISetStoreOptionsType): void | Promise<void>
  // react hook to get the current state of the store.
  useStore: () => Readonly<T>;
  // react hook to select a part of the state.
  useSelector: <R>(selector: (state: T) => R) => Readonly<R>;
}
function createStore<T>(initialState: T | (() => T), options?: ICreateStoreOptions<T>): IStore<T>;

[!WARNING] The store value is immutable(freezed by Object.freeze), do not mutate the store value directly or an error will be thrown.

// always use a new object to update the store value
store.setStore((prev) => ({ ...prev, newItem: 'xxx' }))

isDeepEqual(a, b)

Check if two values are deeply equal, can efficiently compare common data structures like objects, arrays, regexp, date and primitives.

import { isDeepEqual } from 'plain-store';
function isDeepEqual(a: any, b: any): boolean;

isPromiseLike(obj)

Check if a value is a promise

import { isPromiseLike } from 'plain-store';
function isPromiseLike(obj: any): boolean;

License

MIT