An interpreter and a compiler for the Monkey programming language written in Go as described in Ball, T. (2016). Writing An Interpreter In Go. and Ball, T. (2018). Writing A Compiler In Go..
The Monkey programming language has the following features:
- Variable bindings
- Integers, booleans, strings, arrays, and hash maps
- Arithmetic operations
- First-class and higher-order functions
- Built-in functions
- Closures
Below is an excerpt of the language.
// Integers & Booleans
let ispositive = fn(value) {
return value > -1;
};
let crement = fn(value, side) {
if (ispositive(side)) {
return value + 1;
}
return value - 1;
};
puts(crement(0, 1)); // 1
// Strings
let greeting = fn(first, last) {
let begin = "Hello, ";
let end = "!";
if (len(last) > 0) {
return begin + first + " " + last + end;
}
return begin + first + end;
};
puts(greeting("Monkey", "")); // Hello, Monkey!
// Arrays
let accumulate = fn(array, stop) {
if (len(array) == 0) {
return array;
}
if (last(array) == stop) {
return array;
}
let new = push(rest(array), last(array) + 1);
accumulate(new, stop);
};
puts(accumulate([1, 2, 3], 5)); // [3, 4, 5]
// Hash maps
let h = {"foo": 1, true: 2, 3: 3};
puts(h["foo"]); // 1
Execute the below commands in your shell to install monkey.
git clone https://github.com/vincentlabelle/monkey.git
cd monkey
go installThe REPL can be run by executing monkey in your shell (if ~/go/bin is in
your PATH), and you can exit the REPL by typing exit().