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Postings from September 2011
On Mon, Sep 5, 2011 at 2:44 PM, David E. Wheeler <david@kineticode.com> wrote: >> Version objects are far more useful to others who consume $VERSION, >> but module authors may reasonable expect $VERSION not to be modified >> from outside their own code. That was the crux of my argument and >> I'll stick with it, annoyances as you cite to the contrary. > > It seems to me that if you want the original $VERSION, you fetch $Foo::VERSION. Foo->VERSION can meanwhile return a VERSION object. Used to be you could get one or the other, but now you get the same thing from both sources. I find that annoying and, frankly, less useful. Excerpt from <http://www.dagolden.com/index.php/369/version-numbers-should-be-boring/>: $ perl5.8.8 -e '$VERSION=v120.100.103; print main->VERSION' xdg $ perl5.10.0 -e '$version=v120.100.103; print main->version' v120.100.103 [...] $ perl5.8.8 -Mversion -e '$VERSION=v120.100.103; print main->VERSION' v120.100.103 Think about the implications of that for a module called 'Foo'. Even if Foo doesn't use version.pm, if version.pm is loaded anywhere then Foo->VERSION acts differently and gives a different value than is in $Foo::VERSION. *Any* code written expecting the 5.8.8 behavior of ->VERSION breaks in 5.10.0 or even in 5.8.8 if version.pm (prior to 0.92) is loaded by *any* module. Sure, knowing all this, *you* could now choose to fetch $Foo::VERSION or Foo->VERSION, but prior to Perl 5.10.0, no one thought they did anything different, so I don't think it's a good idea to impose new semantics on old code simply for the convenience of today's coder, and certainly not without the deprecation cycle provided for in perlpolicy. I agree that it's a sorry state of affairs, but on this issue, I'm (perhaps shockingly?) in the do-no-harm backward compatibility camp. -- David