Loaf

Loaf is a toy programming language I am currently hacking on to learn some new things. It features a hand written lexer and parser that outputs to a custom bytecode, which is then ran on a stack based virtual machine. Eventually I want to make it output to WebAssembly.

The syntax is a bit of Go, a bit of Ruby and a bit of C.

Building/running

cd src

./all.bash

Or alternatively run the build.bash and run.bash scripts as you need.

Goals

• Type system
  • Properly scope types
  • Do a basic static type check for builtin types (number and bool)
  • Typecheck functions
  • Type aliases
  • Custom type support (structs)
• Functions
  • Store/retrieve globals
    • Create Value table
  • Call frames
  • Execute parameterless, return value-less functions (ie. procedures)
  • Add parameters
  • Return values
• More language features
  • var statement to declare variable by type with a default value
  • && and ||
  • >= and <=
  • Call frames in dynamic list
  • Integer type
  • For loop
  • While loop
  • Else/else-if statements
  • Go style multi-statement if statements
• Another compilation target
  • WebAssembly

Spec

This is a brief rundown of what the language actually is:

// Comments
/* /* nested comments */ */

// Implicit declaration and assignment
x := 100

// Explicit declaration and assignment
var y int = 100

if x == 100 {
  println("Yay!")
}

struct User {
  // public by default fields
  id       int
  username string

  private

  // private fields
  password string
}

// all fields set to their 0 value (0 for ints, "" for strings)
u := User{}

// give public variables values at initialisation
u2 := User{
  id: 101,
  username: "paked"
}

// can have '?' or '!' at end of identifiers, ? implies a boolean return, ! implies mutation
func ready?() bool {
  return false;
}

// declare a 'me?' function on User
func (u *User) me?(id int) bool {
  return u.id == id
}

if u.me?(101) {
  println("I am 101!")
}