Avastha

Avastha is a minimal and flexible state management library for React, with support for both immutable and mutable state updates.

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✨ Features

🍃 Lightweight and dependency-free

🔀 Supports both immutable (setState) and mutable (updateState) updates

🔍 Supports custom selectors, actions, and transformers

🧪 Built with TypeScript in mind, providing robust type safety and inference

⚡️ React 18+ concurrent rendering safe

📦 Installation

npm install avastha
# or
yarn add avastha

🛠️ Usage

1. Basic Counter Example

import { create } from "avastha";

const counterStore = create(({ setState }) => ({
  state: { count: 0 },
  actions: {
    increment: () => setState((s) => ({ count: s.count + 1 })),
    decrement: () => setState((s) => ({ count: s.count - 1 })),
  },
}));

function Counter() {
  const count = counterStore.useState((s) => s.count);
  const increment = counterStore.useAction((a) => a.increment);
  const decrement = counterStore.useAction((a) => a.decrement);

  return (
    <>
      <p>{count}</p>
      <button onClick={increment}>+</button>
      <button onClick={decrement}>-</button>
    </>
  );
}

2. Mutable State Example

const fruitStore = create(({ updateState }) => ({
  state: { fruits: [] },
  actions: {
    addFruit: (name) => updateState((s) => s.fruits.push(name)),
  },
}));

3. Transforms Support

If your store has a transforms object, Avastha will check if your selector returns a transformer function and apply it to the selection.

const userStore = create(({ setState }) => ({
  state: { firstName: "Ada", lastName: "Lovelace" },
  transforms: {
    fullName: ({ firstName, lastName }) => `${firstName} ${lastName}`,
  },
}));

const fullName = userStore.useState((s) => s.fullName); // "Ada Lovelace"

🧩 API

create(initializer, debugFn?) Returns an object with useState and useAction.

useState(selector) Subscribes to a derived slice of state using a selector function.

useAction(selector) Accesses a specific action via a selector function.

🪵 Debugging

Pass a debugFn to create to observe state changes:

const debugFn = (next, prev, updated) => {
  console.log("State changed:", { prev, updated, next });
};
const store = create(initializer, debugFn);

🧪 Example Projects

You can explore more usage examples in the examples/avastha-example directory:

• Basic counter
• Nested state
• Nested state with Transforms
• Multiple slices

📝 License

MIT