From: jim Date: Mon, 6 Apr 2015 09:03:17 +0000 (-0400) Subject: or Haskell X-Git-Url: http://lambda.jimpryor.net/git/gitweb.cgi?a=commitdiff_plain;h=b28c39a60e8ef844710a7194beba5d1b5ae764a4;p=lambda.git or Haskell --- diff --git a/exercises/assignment8-9.mdwn b/exercises/assignment8-9.mdwn index e6d24837..8eb4bc7a 100644 --- a/exercises/assignment8-9.mdwn +++ b/exercises/assignment8-9.mdwn @@ -137,7 +137,7 @@ Return to the original code (that is, before the modifications required by the p -- substitute your own choices for the type Env and value env0 let { xx :: ReaderT Env Maybe Int; xx = return 1 } in runReaderT xx env0 - Okay, here are some questions about various monad transformers. Use OCaml to help you answer them. Which combined monad has the type of an optional list (that is, either `None` or `Some [...]`): an Option transformer wrapped around an underlying List monad, or a List transformer wrapped around an underlying Option monad? Which combined monad has the type of a function from `store`s to a pair `('a list, store)`: a List transformer wrapped around an underlying State monad or a State transformer wrapped around an underlying List monad? + Okay, here are some questions about various monad transformers. Use OCaml or Haskell to help you answer them. Which combined monad has the type of an optional list (that is, either `None` or `Some [...]`): an Option transformer wrapped around an underlying List monad, or a List transformer wrapped around an underlying Option monad? Which combined monad has the type of a function from `store`s to a pair `('a list, store)`: a List transformer wrapped around an underlying State monad or a State transformer wrapped around an underlying List monad? The last two problems are non-monadic.