Implement nice font-lock for LiquidHaskell

[gracjan]

Implement nice font-lock for LiquidHaskell

[gridaphobe]

This would indeed be nice! We have a (possibly outdated) syntax highlighter for vim.

https://github.com/ucsd-progsys/liquid-types.vim/blob/master/haskell.vim#L224-L234

I don't know how portable vim-style highlighters are to emacs font-lock, but it might be a start.

[gracjan]

Thanks. As usual we are waiting on a volunteer. @gridaphobe, maybe you will try?

[alanz]

I think as a start just highlighting the whole comment delimited by {-@ and @-} in a different font would help, never mind the innards of it.

[gracjan]

True. We have code to colorize {-# ... #-} so this could be used to colorize {-@ ... @-}. The biggest problem is not solved though: we have to pick the color! Let the bikeshedding begin :)

[gracjan]

@alanz: Done! Looks already pretty nice!

We can think about deeper annotation highlight later.