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README.md

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 # Type Level Programming
 
+This repository contains a collection of examples demonstrating various type-level programming patterns in Rust, Go, and TypeScript.
+
+The goal of these examples is to show how to leverage the type system of a language to enforce invariants at compile-time, reducing the need for runtime checks and making the code more robust and self-documenting.
+
+## Repository Structure
+
+The examples are organized by language and complexity.
+
+### Rust
+
+The Rust examples demonstrate a progression of state management for a `CredentialManager`:
+
+- **[01-problem](./01-problem)**: The initial problem where state is not managed, allowing operations in any order.
+- **[02-runtime-check](./02-runtime-check)**: Adding runtime checks (e.g., `bool` flags) to ensure operations are performed in the correct state.
+- **[03-builder-pattern](./03-builder-pattern)**: Using separate structs to represent different states, ensuring state transitions are enforced at compile-time.
+- **[04-typestate](./04-typestate)**: A classic implementation of the Typestate pattern using generics and `PhantomData` to track state.
+
+### Go
+
+- **[05-typestate-go-structs](./05-typestate-go-structs)**: Implementing state transitions in Go using separate structs for each state.
+- **[06-typestate-go-interfaces](./06-typestate-go-interfaces)**: Using interfaces to restrict the available methods based on the current state of the object.
+
+### TypeScript
+
+- **[07-typestate-ts](./07-typestate-ts)**: Implementing the Typestate pattern in TypeScript using `this` type parameters to restrict method calls.
+- **[08-type-mapping](./08-type-mapping)**: Mapping enum values (like opcodes) to specific argument types for type-safe messaging.
+- **[09-type-programming](./09-type-programming)**: Advanced recursive type parsing to extract parameters from URL string literals at compile-time.
+
+## Getting Started
+
+### Rust
+You can run the Rust examples using Cargo from the root directory:
+```bash
+# Example: Running the typestate example
+cargo run -p 04-typestate
+```
+
+### Go
+The Go examples can be run using the Go CLI:
+```bash
+go run ./05-typestate-go-structs
+```
+
+### TypeScript
+The TypeScript examples are best viewed in an IDE (like VS Code) to see the type errors and completions. You can also run them using `ts-node`:
+```bash
+npx ts-node 07-typestate-ts/main.ts
+```
+
 ## Sources
 
 - https://www.emoses.org/posts/resolver-resolved-pattern/