ghci with ":set +t" should print type before starting evaluation
Not an actual bug, but questionable design perhaps.
I think this is backwards, as static analysis comes before evaluation, not after:
Prelude> :set +t Prelude> reverse [True] [True] it :: [Bool]
When evaluation raises an exception, no type is printed.
Prelude> :set +t Prelude> True && undefined *** Exception: Prelude.undefined CallStack (from HasCallStack): error, called at libraries/base/GHC/Err.hs:79:14 in base:GHC.Err undefined, called at <interactive>:8:9 in interactive:Ghci4
For teaching (and for my own sanity) I'd much prefer output in logical succession.