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

[GHC]

#1409: Allow recursively dependent modules transparently (without .hs-boot or
anything)
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        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:                    |
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Comment (by bfrk):

 I have gradually changed my opinion on this some over the years. I no
 longer think that writing explicit interface files is too much of a
 burden. Indeed it can have great advantages to do so, but I would prefer a
 proper integration into Haskell the language. The current situation is not
 ideal:

 (1) hs-boot is an obscure name for an interface definition
 (2) it is an implementation defined feature, outside of the language
 (3) it is unclear to me how it interacts with the use of export lists;
 ideally I would want to be able to use interface definition files as an
 alternative to export lists
 (4) it should not be necessary to repeat in the .hs file anything that is
 already fully defined in the interface definition file (incomplete
 definitions are exempted)
 (5) it should be possible to place the interface definition in a
 distinguished "header" part of the .hs, so that it need not be in a
 separate file.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/1409#comment:74>
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