stage 1: a simple compiler

[glaebhoerl]

• Make a Stack project w/ the chosen dependencies
• Make sure they all resolve & build etc.
• Figure out what the initial minimal language will be?
• Make sure LLVM still works w/ the OrcJIT example
• Figure out what a concrete syntax tree should look like as a Haskell type

---

• Write some types?
• Lex something
• Parse something
• Resolve names
• Typecheck something
• Translate to an IR (ANF w/ basic blocks & basic block args?)
  • BBs or EBBs? probably BBs for now to simplify translation to LLVM
• Generate some code
• Output a binary
• Make sure it actually runs & works

---

• Write tests for everything! http://teh.id.au/posts/2017/06/07/round-trip-property/index.html
  • Write pretty printers
    • AST
    • IR
    • Error messages
  • Write well-formedness validators
  • Write a typechecker for the IR as well
  • Write an evaluator
  • Write fizzbuzz
• Write a usable CLI
• Make it JIT
• Go back and fix the fixable FIXMEs and TODOs
• Write a README w/ overview

two types: Int, Bool
arithmetic and comparison operators
if, while; forever/break?
let, var
read(), write()
mutation (assignment)
no functions yet

Example program:

 var n = 0
 forever {
     write(n)
     let m = read()
     if m == 0 {
         return
     }
     n = n + m
 }