deca-memory-utils

A TypeScript utility library providing memory management tools like UniquePtr and SharedPtr for better control over object ownership and lifecycle.

Installation

npm install deca-memory-utils

Features

• UniquePtr: A TypeScript implementation of unique pointer pattern, ensuring single ownership of resources
• SharedPtr: Reference-counted smart pointer implementation for shared resource management
• WeakPtr: Weak reference implementation that doesn't prevent resource cleanup
• Type-safe implementation with full TypeScript support
• Zero dependencies
• Comprehensive test coverage
• Full ESM (ECMAScript Modules) support

Module Support

This package is distributed as an ES Module (ESM). Make sure your project is configured to handle ESM:

// package.json
{
  "type": "module"
}

If you're using TypeScript, ensure your tsconfig.json includes:

{
  "compilerOptions": {
    "module": "esnext",
    "moduleResolution": "node"
  }
}

Usage

UniquePtr Example

import { UniquePtr } from 'deca-memory-utils';

// Create a new unique pointer
const ptr1 = new UniquePtr({ name: "John", data: [1, 2, 3] });

// Access the value
console.log(ptr1.get()); // { name: "John", data: [1, 2, 3] }

// Transfer ownership
const ptr2 = ptr1.move();
console.log(ptr1.get()); // null (ownership transferred)
console.log(ptr2.get()); // { name: "John", data: [1, 2, 3] }

// Reset with new value
ptr2.reset({ name: "Jane", data: [4, 5, 6] });

// Release ownership
const releasedValue = ptr2.release();
console.log(releasedValue); // { name: "Jane", data: [4, 5, 6] }
console.log(ptr2.get()); // null

SharedPtr Example

import { SharedPtr, WeakPtr } from 'deca-memory-utils';

// Create a shared pointer with a destructor
const cleanup = (value: object) => console.log('Cleaning up:', value);
const shared1 = new SharedPtr({ data: "shared resource" }, cleanup);

// Create another reference to the same resource
const shared2 = SharedPtr.fromSharedPtr(shared1);
console.log(shared1.useCount()); // 2

// Create a weak reference
const weak1 = new WeakPtr(shared1);

// Access the value through weak reference
const locked = weak1.lock();
if (locked) {
  console.log(locked.get()); // { data: "shared resource" }
}

// Reset first shared pointer
shared1.reset();
console.log(shared2.useCount()); // 1

// Resource is still alive through shared2
console.log(shared2.get()); // { data: "shared resource" }

// Reset second shared pointer
shared2.reset();
// Destructor is called, resource is cleaned up

// Weak reference is now expired
console.log(weak1.expired()); // true

API Reference

UniquePtr

Constructor

• constructor(value: T | null = null): Creates a new UniquePtr instance

Methods

• get(): T | null: Access the underlying object
• release(): T | null: Release ownership and return the object
• reset(newValue: T | null = null): void: Reset with a new value
• move(): UniquePtr<T>: Transfer ownership to a new UniquePtr

SharedPtr

Constructor

• constructor(value?: NonNullable<T>, destructor?: Destructor<T>): Creates a new SharedPtr instance

Static Methods

• make<T>(value: NonNullable<T>, destructor?: Destructor<T>): SharedPtr<T>: Create a new SharedPtr
• fromSharedPtr<T>(other: SharedPtr<T>): SharedPtr<T>: Create a new SharedPtr from an existing one

Instance Methods

• get(): NonNullable<T> | null: Access the underlying object
• getRaw(): NonNullable<T> | null: Get the raw pointer value
• isValid(): boolean: Check if the pointer is valid
• useCount(): number: Get the current reference count
• reset(value?: NonNullable<T>, destructor?: Destructor<T>): void: Reset with a new value
• swap(other: SharedPtr<T>): void: Swap managed resources with another SharedPtr
• release(): NonNullable<T> | null: Release ownership without calling destructor
• destroy(): void: Destroy the shared pointer and decrement reference count

WeakPtr

Constructor

• constructor(shared?: SharedPtr<T>): Creates a new WeakPtr instance

Methods

• lock(): SharedPtr<T> | null: Create a SharedPtr if resource is still valid
• reset(): void: Reset the weak pointer
• expired(): boolean: Check if the referenced resource has been cleaned up

Project Structure

deca-memory-utils/
├── .gitignore
├── .npmignore
├── package.json
├── tsconfig.json
├── jest.config.cjs
├── README.md
├── LICENSE
├── src/
│   ├── index.ts
│   ├── unique-ptr.ts
│   └── shared-ptr.ts
├── tests/
│   ├── unique-ptr.test.ts
│   └── shared-ptr.test.ts
└── examples/
    ├── unique-ptr-usage.ts
    └── shared-ptr-usage.ts

Development

Prerequisites

• Node.js (v16 or higher recommended)
• npm (v7 or higher)

Setup

# Clone the repository
git clone https://github.com/yourusername/deca-memory-utils.git
cd deca-memory-utils

# Install dependencies
npm install

Scripts

# Run tests (uses Node.js experimental modules support)
npm test

# Build
npm run build

# Lint
npm run lint

Testing

The project uses Jest with ts-jest for testing. The setup includes:

• Full ESM support using Node.js experimental modules
• TypeScript integration via ts-jest
• Test files should use .test.ts extension
• Tests are located in the tests directory

To run tests:

npm test

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

1. Fork the repository
2. Create your feature branch (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

Changelog

[1.1.1] - 2024-11-06

Added

• SharedPtr implementation with reference counting
• WeakPtr implementation for weak references
• Comprehensive memory management features
• Additional test coverage for shared pointer functionality

[1.0.0] - 2024-11-06

Added

• Initial release
• UniquePtr implementation with full TypeScript support
• ESM module configuration
• Basic ownership management functionality
• Prevention of accidental copying
• Comprehensive test suite with Jest
• Example usage code
• Full API documentation

Versioning

This project follows Semantic Versioning. For the versions available, see the tags on this repository.

License

MIT