[Haskell-cafe] Combine `StateT` and `InputT` to maintain state on Ctrl-C interrupt

[Tom Ellis]

On Wed, Aug 12, 2015 at 04:26:59PM +0200, haskell at stefan-klinger.de wrote:
> At first I thought I had stacked the `StateT` and `InputT` in the
> wrong order.  But changing from `InputT (StateT Int IO) ()` to `StateT
> Int (InputT IO) ()` seems not to change anything (which really gives
> me the creeps).

InputT is essentially ReaderT

    http://hackage.haskell.org/package/haskeline-0.7.2.1/docs/src/System-Console-Haskeline-InputT.html#InputT

so it's not surprising that the order has no effect.   Reader commutes with
State.

Tom