[Boost-bugs] [Boost C++ Libraries] #8342: [filesystem] v3 path interface is no longer an abstraction

Subject: [Boost-bugs] [Boost C++ Libraries] #8342: [filesystem] v3 path interface is no longer an abstraction
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-03-27 10:45:30

#8342: [filesystem] v3 path interface is no longer an abstraction
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 Reporter:  alexander.lamaison@…          |       Owner:  bemandawes
     Type:  Bugs                          |      Status:  new       
Milestone:  To Be Determined              |   Component:  filesystem
  Version:  Boost 1.49.0                  |    Severity:  Problem   
 Keywords:                                |  
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 Some of the changes to Boost.Filesystem in v3 have made it into a string
 class with utility methods rather than the path abstraction that it used
 to be.

 Consider:

 path p("/a/b");
 p /= "c";
 cout << p.string();

 In version 2 this would output "/a/b/c" on Windows but now it produces
 "/a/b\c".

 Had the behaviour simple changed from using generic path to always using
 OS path, this would not be a problem; the change would be consistent and
 the chosen string() method would be the only deciding factor deciding in
 what format the path was returned.

 But the behaviour has, instead, changed to return a chimera of generic and
 OS paths which means the output of the string function is now dependent on
 the format of the input string and the modifications that were made during
 its lifetime.  The abstraction has been lost.

 My suggestions:
  - change boost::filesystem::path to have only two string functions: one
 that returns entirely generic paths, the other entirely OS paths
  - make string() be the generic one
  - let no part of the path interface betray the exact separators that
 happen to have been used to construct the string as that is a leaky
 abstraction.

 See original discussion here:
 http://thread.gmane.org/gmane.comp.lib.boost.devel/239446

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8342>
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