[GHC] #1409: Allow recursively dependent modules transparently (without .hs-boot or anything)

[GHC]

#1409: Allow recursively dependent modules transparently (without .hs-boot or
anything)
-------------------------------------+-------------------------------------
        Reporter:  Isaac Dupree      |                Owner:  (none)
            Type:  feature request   |               Status:  new
        Priority:  normal            |            Milestone:  ⊥
       Component:  Compiler          |              Version:  6.10.2
      Resolution:                    |             Keywords:  backpack
Operating System:  Unknown/Multiple  |         Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:  #9256             |  Differential Rev(s):
       Wiki Page:                    |
-------------------------------------+-------------------------------------

Comment (by atravers):

 Replying to [comment:73 simonpj]:
 > I'm not sure which comment you are replying to;
 Darn - I assumed the "comment: 72 in reply to: 49" annotation was enough;
 the comment I was replying to was:
 > Lots of people would like this fixed; but no one has proposed a precise,
 worked-out, *design*. The way lies open!

 Now for the next assumption:
 > and I fear I don't understand what "something like this" is.

 Okay, so I was assuming that the machinery for the "--make" option for GHC
 had some resemblance to computeInOuts in the paper...

 > The big trouble with recursive modules is that: either you need a
 programmer written signature file (i.e. `.hs-boot`) or you have to compile
 all the modules in the SCC at once.  I don't see any other path.

 In 2016, I rebuilt a HBC-based **bubble-gum-and-baling-wire sharp-edges-
 everywhere** implementation which copes with import-recursion (at least
 for what sources I've tested it on so far). The biggest catch?


 == **IT IS SLOW.**

 ...way too slow for practical use (if it only working with Haskell B.
 wasn't - in 2018 - impractical
 enough), hence no download links here or elsewhere. I had been working to
 improve its performance, with little success.

 But if you don't mind "going retro" for a while, I should be able to get
 it working again and send you the sources - just contact me on my GHC-Trac
 email address.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1409#comment:75>
GHC <http://www.haskell.org/ghc/>
The Glasgow Haskell Compiler