Pros of Ramda

• More established and widely adopted in the JavaScript community
• Extensive documentation and examples available
• Simpler learning curve for developers familiar with JavaScript

Cons of Ramda

• Less type safety compared to fp-ts
• Limited support for advanced functional programming concepts
• May require more boilerplate code for complex operations

Code Comparison

Ramda:

const result = R.pipe(
  R.filter(R.propEq('active', true)),
  R.map(R.prop('name')),
  R.sort(R.ascend(R.identity))
)(users);

fp-ts:

import * as A from 'fp-ts/Array'
import * as O from 'fp-ts/Option'
import { pipe } from 'fp-ts/function'

const result = pipe(
  users,
  A.filter((u) => u.active),
  A.map((u) => u.name),
  A.sort(O.getOrd(S.Ord))
)

Both libraries provide functional programming utilities, but fp-ts offers stronger type safety and more advanced FP concepts. Ramda is more accessible for JavaScript developers, while fp-ts caters to those seeking a more rigorous functional approach with TypeScript integration. The code comparison demonstrates how both libraries handle common operations like filtering, mapping, and sorting, with fp-ts showcasing its type-safe approach and Ramda its more JavaScript-like syntax.

Pros of Sanctuary

• More beginner-friendly with extensive documentation and examples
• Stricter runtime type checking for enhanced safety
• Smaller API surface, potentially easier to learn and use

Cons of Sanctuary

• Less frequently updated compared to fp-ts
• Smaller ecosystem and community support
• May have performance overhead due to runtime type checking

Code Comparison

Sanctuary:

S.map(S.add(1), [1, 2, 3])

fp-ts:

import { array } from 'fp-ts'
import { pipe } from 'fp-ts/function'

pipe([1, 2, 3], array.map(n => n + 1))

Key Differences

• Sanctuary focuses on runtime type checking, while fp-ts leverages TypeScript's static typing
• fp-ts has a larger API surface with more advanced functional programming concepts
• Sanctuary aims for simplicity and safety, while fp-ts prioritizes performance and flexibility

Use Cases

• Choose Sanctuary for projects prioritizing runtime safety and simplicity
• Opt for fp-ts in TypeScript projects requiring advanced FP concepts and performance

Both libraries provide functional programming tools for JavaScript, but they cater to different preferences and requirements. The choice between them depends on project needs, team expertise, and desired balance between safety and performance.

Pros of fantasy-land

• Provides a specification for algebraic structures in JavaScript
• Language-agnostic, allowing implementations in various JS flavors
• Widely adopted standard in the functional programming community

Cons of fantasy-land

• Primarily a specification, not a full implementation
• Requires additional libraries or custom code for practical use
• May have a steeper learning curve for developers new to algebraic structures

Code Comparison

fantasy-land (specification):

const Functor = {
  map: (f) => (fa) => /* ... */
};

fp-ts (implementation):

const array = {
  map: <A, B>(f: (a: A) => B) => (fa: Array<A>): Array<B> =>
    fa.map(f)
};

Key Differences

• fp-ts provides a comprehensive implementation of functional programming concepts
• fantasy-land focuses on standardizing interfaces for algebraic structures
• fp-ts is TypeScript-centric, while fantasy-land is language-agnostic
• fp-ts offers more out-of-the-box functionality and utilities
• fantasy-land allows for more flexibility in implementation across different libraries

Both projects contribute significantly to functional programming in JavaScript, with fp-ts offering a more complete toolkit and fantasy-land providing a common specification for interoperability between libraries.

Pros of Lodash

• Widely adopted and well-established utility library
• Extensive collection of functions for common programming tasks
• Easier learning curve for developers familiar with imperative programming

Cons of Lodash

• Less emphasis on functional programming concepts
• Limited support for advanced type safety and inference
• May encourage a more imperative coding style

Code Comparison

fp-ts example:

import { pipe } from 'fp-ts/function'
import { map, filter } from 'fp-ts/Array'

const result = pipe(
  [1, 2, 3, 4, 5],
  filter(n => n % 2 === 0),
  map(n => n * 2)
)

Lodash example:

import _ from 'lodash'

const result = _.chain([1, 2, 3, 4, 5])
  .filter(n => n % 2 === 0)
  .map(n => n * 2)
  .value()

Summary

fp-ts focuses on functional programming principles and leverages TypeScript's type system for enhanced safety. It provides a more rigorous approach to functional programming but may have a steeper learning curve.

Lodash offers a broader set of utility functions and is more accessible to developers with various programming backgrounds. However, it may not provide the same level of type safety and functional programming support as fp-ts.

The choice between the two libraries depends on the project requirements, team expertise, and desired programming paradigm.

Pros of Folktale

• Simpler API and easier learning curve for beginners
• More idiomatic JavaScript approach
• Better documentation with clear examples and use cases

Cons of Folktale

• Smaller ecosystem and community compared to fp-ts
• Less comprehensive in terms of functional programming constructs
• Not as actively maintained as fp-ts

Code Comparison

Folktale:

const { Result } = require('folktale');

const divide = (a, b) =>
  b === 0 ? Result.Error('Division by zero') : Result.Ok(a / b);

divide(10, 2).map(x => x * 2).getOrElse(0);

fp-ts:

import { pipe } from 'fp-ts/function';
import * as E from 'fp-ts/Either';

const divide = (a: number, b: number): E.Either<string, number> =>
  b === 0 ? E.left('Division by zero') : E.right(a / b);

pipe(divide(10, 2), E.map(x => x * 2), E.getOrElse(() => 0));

Both libraries provide similar functionality for handling computations that may fail, but fp-ts offers a more type-safe approach with its TypeScript integration. Folktale's API is more straightforward, while fp-ts provides a more comprehensive set of functional programming tools.

Pros of monet.js

• Simpler API with fewer concepts to learn
• More beginner-friendly documentation
• Smaller bundle size, potentially better for lightweight applications

Cons of monet.js

• Less comprehensive type system compared to fp-ts
• Fewer advanced functional programming features
• Less active development and community support

Code Comparison

monet.js:

const result = Maybe.fromNull(someValue)
  .map(x => x * 2)
  .orElse('default');

fp-ts:

import { pipe } from 'fp-ts/function'
import * as O from 'fp-ts/Option'

const result = pipe(
  O.fromNullable(someValue),
  O.map(x => x * 2),
  O.getOrElse(() => 'default')
)

Both libraries provide similar functionality for handling optional values, but fp-ts offers more type safety and composability at the cost of increased verbosity. monet.js has a more concise syntax, which may be preferable for simpler use cases or developers new to functional programming. However, fp-ts provides a more robust ecosystem and better integration with TypeScript, making it a stronger choice for larger, more complex projects.