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  "path": "/t/fancy-haskell-advice-add-recursion-to-a-strongly-typed-stack-machine/13607#post_8",
  "publishedAt": "2026-03-12T23:18:12.000Z",
  "site": "https://discourse.haskell.org",
  "tags": [
    "github.com/AriFordsham/stack-machine",
    "src/StackMachine.hs",
    "`main`",
    "show original"
  ],
  "textContent": "So I have worked out the scheme I want and implemented it, so far without compile-time stack-underflow guarantees. They will be an interesting challenge to add, any pointers appreciated!\n\ngithub.com/AriFordsham/stack-machine\n\n#### src/StackMachine.hs\n\n`main`\n\n\n    {-# LANGUAGE ImpredicativeTypes #-}\n    {-# LANGUAGE RecordWildCards #-}\n    {-# LANGUAGE TypeFamilies #-}\n\n    module StackMachine where\n\n    import Data.Bits ((.&.))\n    import Data.List (uncons)\n\n    import Data.Foldable (foldlM)\n\n    import Control.Monad.Identity (Identity)\n\n    import Data.Fin (Fin, fin0, fin1, fin2, fin3, fin4)\n    import Data.Type.Nat (Nat (S), Nat1, Nat5)\n    import Data.Vec.Lazy (Vec (..), (!))\n\n    data Instr = And | Add | Eq | Dup | Swap | Push Int | Pop\n      deriving (Show)\n\n\n\nThis file has been truncated. show original",
  "title": "Fancy Haskell advice: Add recursion to a strongly-typed stack machine"
}