Because time 1.4 is a boot library for GHC 7.8, we will support the
compatibility module as long as we support 7.8. But we should be clear
about when we will no longer need it.
We already lower-bound tagsoup at 0.13.7, which means we were always
running the compatibility layer (it was conditional on min value
0.13). Better to just use `lookupEntity` from the library directly, and
convert a string to a char if need be.
Don't use custom prelude for latest ghc.
This is a better approach to making 'stack ghci' and 'cabal repl'
work. Instead of using NoImplicitPrelude, we only use the custom
prelude for older ghc versions. The custom prelude presents a
uniform API that matches the current base version's prelude.
So, when developing (presumably with latest ghc), we don't
use a custom prelude at all and hence have no trouble with ghci.
The custom prelude no longer exports (<>): we now want to
match the base 4.8 prelude behavior.
- The (non-exported) prelude is in prelude/Prelude.hs.
- It exports Monoid and Applicative, like base 4.8 prelude,
but works with older base versions.
- It exports (<>) for mappend.
- It hides 'catch' on older base versions.
This allows us to remove many imports of Data.Monoid
and Control.Applicative, and remove Text.Pandoc.Compat.Monoid.
It should allow us to use -Wall again for ghc 7.10.
mtl switched from ErrorT to ExceptT, but we're not sure which mtl we'll
be dealing with. This should make errors work with both.
The main difference (beside the name of the module and the monad
transformer) is that Except doesn't require an instance of an Error
Typeclass. So we define that for compatability. When we switch to a
later mtl, using Control.Monad.Exception, we can just erase the instance
declaration, and all should work fine.