This repo contains an implementation of the monkey language specified by this book : https://interpreterbook.com/
It is the result of my progress with said book.
Build and Test status :
Progress:
- Implemented a Lexer. (With tests)
- Implemented Parser (With Tests)
- Implemented Evaluation (With Tests)
- Additions to the Original
Monkey looks like the following:
// Bind values to names with let-statements
let version = 1;
let name = "Monkey programming language";
let myArray = [1, 2, 3, 4, 5];
let coolBooleanLiteral = true;
// Use expressions to produce values
let awesomeValue = (10 / 2) * 5 + 30;
let arrayWithValues = [1 + 1, 2 * 2, 3];
Monkey also supports function literals and we can use them to bind a function to a name
// Define a `fibonacci` function
let fibonacci = fn(x) {
if (x == 0) {
0 // Monkey supports implicit returning of values
} else {
if (x == 1) {
return 1;// ... and explicit return statements
} else {
fibonacci(x - 1) + fibonacci(x - 2); // Recursion! Yay!
}
}
};
... the data types it supports are : booleans, strings, hashes, integers and arrays. We can combine them!
// Here is an array containing two hashes, that use strings as keys and integers
// and strings as values
let people = [{"name": "Anna", "age": 24}, {"name": "Bob", "age": 99}];
// Getting elements out of the data types is also supported.
// Here is how we can access array elements by using index expressions:
fibonacci(myArray[4]);
// => 5
// We can also access hash elements with index expressions:
let getName = fn(person) { person["name"]; };
// And here we access array elements and call a function with the element as
// argument:
getName(people[0]); // => "Anna"
getName(people[1]); // => "Bob"