On Jul 22, 2020, at 1:43 PM, Joachim Breitner <mail@joachim-breitner.de> wrote:

Just as a note, I never quite understood how we plan to implement
#229---is it supposed to be done through state in the lexer, or do we
have a simple lexer that keeps all tokens, including white space, and
then write a post-processing function to glue and rejigger tokens?

No idea here.

#229 is in fact already implemented: https://gitlab.haskell.org/ghc/ghc/-/merge_requests/1664   I don't remember the details to explain them, but I don't think it turned out hard to implement.

Richard