Add exact print proposal

[jappeace]

No description provided.

[ulysses4ever]

@jappeace could you explain what's the relation to the earlier HF proposal?

[Mikolaj]

@jappeace could you explain what's the relation to the earlier HF proposal?

The start of the document says "Note that this is a copy of the TWG proposal: haskellfoundation/tech-proposals#6", but indeed I'm curious how literally this is a copy, in particular, if the experience gained when implementing and discussing lead to some modifications or maybe if this is the baseline over which the modifications are expected to be made.

[ulysses4ever]

There's probably no harm in copying old stuff, but I personally hoped that we can make some profit out of our process and discuss some details that poped up during the past couple months in a new document. If creating a whole new document sounds like too much, a new section in the copy would be fine as well...

[jappeace]

I put the somewhat relevant parts of TWG proposal into the relevant sections of the cabal proposal template.
and filled out some other headings, especially open questions is a fair bit different now.

unlike the original proposal says, the common stanzas have been investigated here:
haskell/cabal#11277

and unlike the original proposal says, comment parsing is now pretty solid with this PR:
haskell/cabal#11252
(my zurich hack prototype did only one or two locations, leana made it work for basically any valid position).

I think these are the only two major implementation issues left from the original TWG proposal:

+ Add support for comma printing.
+ add support for conditional branches.
  See the technical content section for more details on this.

Both of these are investigated by a prototype focussing on "trivia", because FieldGrammar handles both conditionals as well as the comma's.
haskell/cabal#11227 (comment)