[GHC] #2550: Add an option to use manifest files instead of filesystem hierarchy to find modules

[GHC]

#2550: Add an option to use manifest files instead of filesystem hierarchy to find
modules
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    Reporter:  YitzGale         |       Owner:          
        Type:  feature request  |      Status:  new     
    Priority:  normal           |   Component:  Compiler
     Version:  6.9              |    Severity:  normal  
    Keywords:                   |    Testcase:          
Architecture:  Unknown          |          Os:  Unknown 
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 As discussed in the following thread:

 http://www.haskell.org/pipermail/haskell-cafe/2008-August/046494.html

 Add an option to look for modules using manifest files,
 rather than assuming that the filesystem contains a hierarchy
 of directories that exactly matches the module hierarchy.

 This is desirable for the following reasons:

  * It avoids an ugly and ad hoc dependency between two unrelated domains.
  * In large and complex projects, it allows the project manager more
 flexibility in using directory structure to organize teams and manage
 complex version control setups.
  * It avoids problems caused by mismatch between the filesystem and the
 module hierarchy, such as a non-hierarchical file system or
 incompatibilities in the way files are named.
  * It allows for more than one module per file. This is helpful because
 the module system is the only way to achieve encapsulation in Haskell, so
 the system needs to be as lightweight and flexible as possible. It also
 makes it easier to share and distribute Haskell programs when it is most
 convenient to do so as a single file, such as literate Haskell via email.

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/2550>
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