Pros of Bacon.js

• More mature and established project with a larger community
• Extensive documentation and examples available
• Better integration with jQuery and other DOM libraries

Cons of Bacon.js

• Larger file size and potentially slower performance
• Less frequent updates and maintenance
• More complex API, which can be harder for beginners to grasp

Code Comparison

Bacon.js:

Bacon.fromEvent(document, 'click')
  .map(e => e.clientX)
  .filter(x => x > 100)
  .onValue(x => console.log(x));

Kefir:

Kefir.fromEvents(document, 'click')
  .map(e => e.clientX)
  .filter(x => x > 100)
  .onValue(x => console.log(x));

Both libraries offer similar functionality for handling event streams, but Kefir's API is generally more concise and easier to understand. Bacon.js provides more built-in methods and operators, which can be beneficial for complex scenarios but may increase the learning curve for new users.

Kefir focuses on performance and simplicity, making it a good choice for projects where minimizing bundle size and maximizing speed are priorities. Bacon.js, on the other hand, offers a more comprehensive set of features and better integration with existing libraries, which can be advantageous for larger, more complex applications.

Pros of RxJS

• Larger ecosystem and community support
• More comprehensive set of operators and utilities
• Better integration with Angular framework

Cons of RxJS

• Steeper learning curve due to its complexity
• Larger bundle size, which may impact performance
• More verbose syntax for some operations

Code Comparison

RxJS:

import { of } from 'rxjs';
import { map } from 'rxjs/operators';

of(1, 2, 3).pipe(
  map(x => x * 2)
).subscribe(console.log);

Kefir:

const Kefir = require('kefir');

Kefir.sequentially(100, [1, 2, 3])
  .map(x => x * 2)
  .onValue(console.log);

Key Differences

• RxJS uses a pipe method for chaining operators, while Kefir allows direct chaining
• RxJS has a more extensive set of operators, but Kefir's API is often simpler
• Kefir focuses on performance and a smaller footprint, while RxJS prioritizes feature completeness

Use Cases

• RxJS: Large-scale applications, especially those using Angular
• Kefir: Projects prioritizing performance and simplicity, or those with size constraints

Both libraries provide powerful tools for reactive programming, with RxJS offering more features at the cost of complexity, while Kefir aims for simplicity and performance.

Pros of xstream

• Smaller bundle size and lighter weight than Kefir
• Designed specifically for Cycle.js, offering seamless integration
• Simpler API with fewer operators, making it easier to learn and use

Cons of xstream

• Less comprehensive set of operators compared to Kefir
• Smaller community and ecosystem than Kefir
• Limited compatibility with other libraries and frameworks

Code Comparison

xstream:

import xs from 'xstream';

const stream = xs.periodic(1000).map(i => i * 2);
stream.addListener({
  next: i => console.log(i),
  error: err => console.error(err),
  complete: () => console.log('completed')
});

Kefir:

import Kefir from 'kefir';

const stream = Kefir.interval(1000).map(i => i * 2);
stream.onValue(i => console.log(i));
stream.onError(err => console.error(err));
stream.onEnd(() => console.log('completed'));

Both libraries provide similar functionality for creating and manipulating streams. xstream uses a more concise syntax with a single addListener method, while Kefir separates event handling into distinct methods. xstream's approach may be more intuitive for beginners, while Kefir's approach offers more flexibility in handling different event types.

Pros of most

• Higher performance and lower memory usage
• More comprehensive and well-documented API
• Better support for advanced functional programming concepts

Cons of most

• Steeper learning curve for beginners
• Less active community and fewer updates in recent years
• More complex setup and configuration

Code Comparison

most:

import { from, map, filter } from 'most'

from([1, 2, 3, 4])
  .map(x => x * 2)
  .filter(x => x > 5)
  .observe(x => console.log(x))

Kefir:

import Kefir from 'kefir'

Kefir.sequentially(100, [1, 2, 3, 4])
  .map(x => x * 2)
  .filter(x => x > 5)
  .onValue(x => console.log(x))

Both most and Kefir are reactive programming libraries for JavaScript, but they have different approaches and strengths. most focuses on high performance and advanced functional programming concepts, making it suitable for complex applications with demanding requirements. Kefir, on the other hand, offers a more approachable API and active community support, making it a good choice for developers new to reactive programming or smaller projects.

The code comparison shows that both libraries provide similar functionality for creating and manipulating streams of data. However, most's API is more concise and functional, while Kefir's API is more intuitive for developers familiar with other reactive libraries.

Pros of Callbag

• Lightweight and modular design, allowing for smaller bundle sizes
• More flexible and extensible, supporting both push and pull-based streams
• Language-agnostic protocol, enabling implementation in various programming languages

Cons of Callbag

• Steeper learning curve due to its lower-level nature
• Less comprehensive documentation and smaller ecosystem compared to Kefir
• Requires more boilerplate code for basic operations

Code Comparison

Kefir:

const stream = Kefir.sequentially(1000, [1, 2, 3])
  .map(x => x * 2)
  .filter(x => x > 2)
  .onValue(console.log)

Callbag:

const source = interval(1000)
pipe(
  source,
  map(x => x * 2),
  filter(x => x > 2),
  forEach(console.log)
)

Both examples create a stream of values, double them, filter values greater than 2, and log the results. Callbag requires importing and using separate utility functions, while Kefir provides a more fluent API. Kefir's approach may be more intuitive for developers familiar with reactive programming, while Callbag offers more granular control at the cost of verbosity.

Pros of proposal-observable

• Standardized approach, potentially becoming part of ECMAScript
• Simpler API with fewer methods, focusing on core functionality
• Wider adoption potential due to TC39 backing

Cons of proposal-observable

• Less mature and feature-rich compared to Kefir
• Lacks some advanced operators and combinators present in Kefir
• Still in proposal stage, not yet finalized or widely implemented

Code Comparison

Kefir:

const stream = Kefir.fromEvents(button, 'click')
  .debounce(250)
  .map(e => e.target.value)
  .filter(value => value.length > 3)
  .onValue(value => console.log(value));

proposal-observable:

const observable = new Observable(observer => {
  const handler = e => observer.next(e.target.value);
  button.addEventListener('click', handler);
  return () => button.removeEventListener('click', handler);
});

Note: The proposal-observable example is more basic, as it doesn't include built-in operators like debounce, map, or filter. These would need to be implemented separately or through additional libraries.