Frontend Plugins Proposal

[Matthew Pickering]

4 years ago Edsko proposed a patch to add support for frontend plugins
to GHC. You can read his proposal here -
https://ghc.haskell.org/trac/ghc/wiki/FrontendPluginsProposal#no1

Something like core to core plugins but for typechecked code would be
useful for tool writers. Does anyone know why the patch was never
merged?

Confusingly Edward Yang implemented another feature called frontend
plugins which does something quite different (allowing users to write
custom major modes rather than hook into the frontend). These features
are quite different to each other.

Thanks,

Matt