Introduction

monkey-rs is a Rust implementation of the Monkey programming language from Thorsten Ball's Writing An Interpreter In Go.

"But why the name? Why is it called "Monkey"? Well, because monkeys are magnificent, elegant, fascinating and funny creatures. Exactly like our interpreter" — Thorsten Ball

What is Monkey?

Monkey is a programming language designed to teach the fundamentals of interpreter construction. It features:

• C-like syntax that's familiar and easy to read
• Variable bindings with let statements
• Integers and booleans as basic data types
• Arithmetic expressions with standard operators
• Built-in functions for common operations
• First-class and higher-order functions supporting functional programming
• Closures that capture their environment
• String data type with built-in functions
• Array data type with built-in functions
• Hash data type for key-value storage

Getting Started

To start using monkey-rs, you can run the interactive REPL:

cargo run

This will launch the Monkey REPL where you can experiment with the language interactively.

Example Program

Here's a simple example of Monkey code:

let fibonacci = fn(x) {
  if (x == 0) {
    0
  } else {
    if (x == 1) {
      1
    } else {
      fibonacci(x - 1) + fibonacci(x - 2);
    }
  }
};

fibonacci(10); // => 55

This documentation will guide you through all the features and capabilities of the Monkey programming language as implemented in Rust.