Which takes priority site\lib or lib?

BrowserUk has asked for the wisdom of the Perl Monks concerning the following question:

I just installed Test::Simple 0.98 for a package that is dependent on Test::More 0.98:

But when I try the install of the dependent package it complains:

Warning: prerequisite Test::More 0.98 not found. We have 0.96.
[download]

So then I go looking an find Test::More is installed in both lib and site\lib:

C:\perl64>attrib /s more.pm
A       I    C:\perl64\cpan\build\BerkeleyDB-0.43-qD7hPx\t\Test\More.p
+m
A       I    C:\perl64\cpan\build\ExtUtils-MakeMaker-6.62-sv1XY8\t\lib
+\Test\More.pm
A    R  I    C:\perl64\lib\Test\More.pm <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
A       I    C:\perl64\packages\BerkeleyDB-0.43\t\Test\More.pm
A       I    C:\perl64\packages\DB_File-1.820\db-5.1.19\lang\perl\Berk
+eleyDB\t\Test\More.pm
A       I    C:\perl64\packages\ExtUtils-MakeMaker-6.50\t\lib\Test\Mor
+e.pm
A    R  I    C:\perl64\packages\Test-Simple-0.94\blib\lib\Test\More.pm
A       I    C:\perl64\packages\Test-Simple-0.94\lib\Test\More.pm
A    R  I    C:\perl64\packages\Test-Simple-0.96\blib\lib\Test\More.pm
A       I    C:\perl64\packages\Test-Simple-0.96\lib\Test\More.pm
A    R  I    C:\perl64\packages\Test-Simple-0.98\blib\lib\Test\More.pm
A       I    C:\perl64\packages\Test-Simple-0.98\lib\Test\More.pm
A       I    C:\perl64\packages\Win32-Unicode-0.24\inc\Test\More.pm
A    R  I    C:\perl64\site\lib\Test\More.pm   <<<<<<<<<<<<<<<<<<<<<<<
+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<
[download]

Looking inside the two more.pms, the lib is 0.98 and site\lib is 0.96.

Which means site\lib overrides lib?

And why has it suddenly started installing itself in a different place?

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Comment on Which takes priority site\lib or lib? Select or Download Code

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Re: Which takes priority site\lib or lib? by moritz (Cardinal) on Feb 23, 2013 at 14:51 UTC
On newish perls (I'd guess since perl 5.12, but I could be wrong), site/lib takes precedence over lib, to allow "overwriting"/shadowing/updating of core modules without touching the core package. And why has it suddenly started installing itself in a different place? The idea is that package managers (like activestate's ppm, or debian's dpkg) install into lib/, and CPAN installers into site/lib. Since the "Reveal this spoiler" link doesn't work for me (says "No such parent node"), I can't tell whether it worked as expected. Perl 6 - the future is here, just unevenly distributed	[reply]
Re^2: Which takes priority site\lib or lib? by BrowserUk (Patriarch) on Feb 23, 2013 at 14:58 UTC
On newish perls (I'd guess since perl 5.12, but I could be wrong), site/lib takes precedence over lib So they silently broke older installs without a by, leave or warning. Perfect. (No wonder Perl5's dying. :( ) With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re^3: Which takes priority site\lib or lib? by moritz (Cardinal) on Feb 23, 2013 at 17:20 UTC
So they silently broke older installs Well, old installations usually don't magically get a new perl. When installing a new major version of perl 5, it's a good idea to re-install all dependent modules anyway. And it wasn't without warning either. To quote perl5120delta: In `@INC`, `ARCHLIB` and `PRIVLIB` now occur after after the current version's `site_perl` and `vendor_perl`. Modules installed into `site_perl>`and `vendor_perl` will now be loaded in preference to those installed in `ARCHLIB` and `PRIVLIB`. Perl 6 - the future is here, just unevenly distributed	[reply] [d/l] [select]
Re^4: Which takes priority site\lib or lib? by BrowserUk (Patriarch) on Feb 23, 2013 at 17:41 UTC
Re: Which takes priority site\lib or lib? (core/dual-lived/INSTALLDIRS) by Anonymous Monk on Feb 23, 2013 at 20:30 UTC
It is a common and stupid bug with dual-lived modules , if you look around, I'll bet you'll find more 2006 Bug #25163 for Test-Simple: Set INSTALLDIRS = perl for 5.6.2 2010 Bug #57201 for CPANPLUS: installdirs should be site when > perl 5.11 If you're sticking with perl $] >= 5.009005 && $] <= 5.011000 you can isolate yourself from these Makefile.PL oversights with perl Makefile.PL INSTALLDIRS=perl or, even though no core modules use it, perl Build.PL installdirs=core	[reply]
Re^2: Which takes priority site\lib or lib? (core/dual-lived/INSTALLDIRS) by BrowserUk (Patriarch) on Feb 23, 2013 at 20:41 UTC
you can isolate yourself from these Makefile.PL oversights with perl Makefile.PL INSTALLDIRS=perl That seems to work. Many thanks for the work around. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply]
Re: Which takes priority site\lib or lib? by manorhce (Beadle) on Feb 23, 2013 at 14:25 UTC
Hi BrowerUk Can you please provide the list of paths your @INC contains it is based on the stack of @INC list which comes first the lib path comes first, for which we are using unshift with @INC to put the path to search first	[reply]
Re^2: Which takes priority site\lib or lib? by BrowserUk (Patriarch) on Feb 23, 2013 at 14:33 UTC
C:\perl64\packages\Inline-CPP-0.42>perl -V Summary of my perl5 (revision 5 version 10 subversion 1) configuration +: Platform: osname=MSWin32, osvers=5.2, archname=MSWin32-x64-multi-thread ... Characteristics of this binary (from libperl): Compile-time options: MULTIPLICITY PERL_DONT_CREATE_GVSV PERL_IMPLICIT_CONTEXT PERL_IMPLICIT_SYS PERL_MALLOC_WRAP PL_OP_SLAB_ALLOC USE_64_BIT_I +NT USE_ITHREADS USE_LARGE_FILES USE_PERLIO USE_SITECUSTOMIZE Locally applied patches: ActivePerl Build 1007 [291969] 0abd0d disable non-unicode case insensitive trie matching Built under MSWin32 Compiled at Jan 27 2010 14:12:21 @INC: c:/perl64/site/lib c:/perl64/lib . [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]
Re: Which takes priority site\lib or lib? by Anonymous Monk on Feb 24, 2013 at 17:45 UTC
Installation-directory choices never have anything to do with @LIB, only with environment-variables and/or CPAN defaults (which in the end do the same thing).	[reply]
Re^2: Which takes priority site\lib or lib? by BrowserUk (Patriarch) on Feb 24, 2013 at 18:00 UTC
Installation-directory choices never have anything to do with @LIB, I didn't mention `@LIB`? only with environment-variables and/or CPAN defaults If you know of a reference that details those, that would be useful information. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l]

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