schtate

Functional Wrappers for State Management

This library offers algebraic data types for managing state.

Motivation

Don't worry, if you aren't familiar with algebraic data types, this library is designed to be easy to consume regardless of prior functional programming experience.

I think it's safe to say that arrays are the most heavily leaned upon data structure we have in JavaScript/Typescript. This is because the JS language was modified to include a rich API for arrays. This API is inspired heavily by functional programming. You can write pure functions that act on each item of your array (if there are any) and you get a new copy of the array with each one. Even when modeling data as an object, it's common to convert the object to an array to iterate over it. Schtate aims to make it as easy to work with other types of data as it is to work with arrays.

Do I need to know Functional Programming to use schtate?

Inheriting code that uses FP can be daunting, as it can look quite different from imperative code. Composing functions into pipelines is pretty convenient, but if you aren't used to seeing it, it can be daunting and hard to read.

Schtate is designed to be easy to read and write to anybody who is familiar with Arrays and Promises. It is unlikely to be a full replacement for functional programming libraries like fp-ts or ramda.

ESM Usage

schtate is built with ESM (ECMAScript Modules) support and works with modern bundlers like Vite, Rollup, and webpack.

Importing

// Import from the root package
import { Maybe, State, Either } from "schtate";

// Or import specific modules
import { Maybe } from "schtate";

TypeScript Configuration

For optimal TypeScript support, ensure your tsconfig.json includes:

{
  "compilerOptions": {
    "module": "esnext",
    "moduleResolution": "node16",
    "esModuleInterop": true
  }
}

Common Issues

1. Module Resolution Errors

   • If you encounter module resolution errors, ensure you're using a bundler that supports ESM
   • Clear your node_modules and reinstall dependencies
   • Verify your bundler's configuration supports ESM imports

2. TypeScript Path Resolution

   • If TypeScript can't find the types, ensure skipLibCheck is set to true in your tsconfig.json
   • The package includes type definitions in the build/types directory

Supported Environments

• Node.js 14+
• Modern browsers (with bundler)
• Vite
• Remix
• Next.js
• Rollup
• webpack 5+

Documentation

State

Maybe

Bool

Either

Result

Validation

Effect