The Monkey Language Interpreter

Go言語でつくるインタプリタ

This is an interpreter for the Monkey language. Try REPL.

$ go get -u github.com/raahii/monkey-interpreter

❯ monkey
Hello, ${username}! This is the Monkey programming language!
Feel free to type in commands
>> 5
5
>> -5
-5
>> 2 * (3 + 2) / 3
3
>> let x = 3
>> if ( x > 5 ) { true } else { false }
false
>> let add = fn(x, y) { return x + y; };
>> add(x, 5)
8
>> let newAdder = fn(x) { fn(y) { return x + y } };
>> let addTwo = newAdder(2);
>> addTwo(x);
5

Monkey Language

• integer, boolean, string, array, hash
• +, -. *, /, (, )
• puts(<string>), len(<array>), first(<array>), last(array), rest(<array>)

Lexer (chapter1)

Parser (chapter2)

Evaluator (chapter3)

Updated interpreter (chapter4)

• Add support for new literals and builtin functions.

  • String (litral, +)
  • Array (literal, indexing, len(), push(), first(), rest(), last())
  • Hash (literal, indexing)
  • puts()