Interpreter for a made-up language written in Go.

• Finish basic functions of the lexer
• A REPL
• Write a parser
  • AST
• Evaluate expressions
• Add more data types and built-in functions to the interpreter (arrays, hashes, etc.)

let five = 5; 
let ten = 10; 
let add = fn(x, y) { 
 x + y; 
}; 
let result = add(five, ten);