ELox/README.md

# ELox

A Lox variant for embedded devices.
It's sole purpose is to be a playground to implement an
end to end compiler for embedded devices.

## Features

ELox omits some features from Lox and borrows some others from C.
The feature set is meant to be restrictive to ease implementation.

- Static typing with no type inference.
- Words (`word`), and boolean (`true` and `false`) types.
- Word literals in different formats: `101`, `0x101`, `0b101`, `0o101`.
- Arithmetic expressions: `+`, `-`, `*`, `<<`, `>>`.
- Logical expressions: `&&`, `||`, `==`, `!=`, `<`, `<=`, `>`, `>=`.
- Bitwise expressions: `&`, `|`, `^`.
- Stack and global variables: `var myWord word`.
- Control flow with `if`, `while` and `for` with usual C-like syntax.
- Memory regions which can be used to access a group of registers more effectively.
  They must be instantiated at a particular address and all elements are words.
  ```
  mem someRegGroup {
    reg1
    reg2
    reg3
  }

  var regs someRegGroup = @0xdfffffff

  fun main () {
    regs.reg1 = 0xff
    var test word = regs.reg2
  }
  ```
- Functions
  ```
  // This is a comment btw.
  fun myFunWithReturn(arg1 word, arg2 bool) word {
    var res word = 0
    if (arg2) {
        res = arg1
    } else {
        res = arg1 * arg1
    }
  }

  fun myFun(arg1 word, arg2 word) {
    doSomethingElse(arg1, arg2)
  }
  ```

Notable ommisions are signed integers, heap variables (no malloc implementation yet),
arrays, structs and strings. These may be slowly implemented as needs arise.