[Haskell-cafe] Correct parsers for bounded integral values

[Jeff Clites]

> On Jul 21, 2025, at 8:43 AM, Stefan Klinger <haskell at stefan-klinger.de> wrote:
> 
> Hallo, and thanks for the discussion!

You are welcome!

> But there is a *different* read function
> 
>    read :: String -> Word8
> 
> which is not used in the scenario above, and this is the buggy one
> (and all its bounded cousins).

I think you will find, though, that `read @Word8` is intended to match the behavior of `(fromInteger @Word8) . (read @Integer)`. At least, the `Int` case is specified in the Haskell Report (in the Prelude implementation).

But I could be wrong about the intention in the other cases, you can always ask the relevant committee.

(BTW the `read` functions have other quirks, like allowing leading whitespace.)

Jeff Clites