NAME

       lib::core::only - Remove all non-core paths from @INC to avoid site/vendor dirs

SYNOPSIS

         use lib::core::only; # now @INC contains only the two core directories

       To get only the core directories plus the ones for the local::lib in scope:

         $ perl -Mlib::core::only -Mlocal::lib=~/perl5 myscript.pl

       To attempt to do a self-contained build (but note this will not reliably propagate into
       subprocesses, see the CAVEATS below):

         $ PERL5OPT='-Mlib::core::only -Mlocal::lib=~/perl5' cpan

DESCRIPTION

       lib::core::only is simply a shortcut to say "please reduce my @INC to only the core lib
       and archlib (architecture-specific lib) directories of this perl".

       You might want to do this to ensure a local::lib contains only the code you need, or to
       test an App::FatPacker tree, or to avoid known bad vendor packages.

       You might want to use this to try and install a self-contained tree of perl modules. Be
       warned that that probably won't work (see "CAVEATS").

       This module was extracted from local::lib's --self-contained feature, and contains the
       only part that ever worked. I apologise to anybody who thought anything else did.

CAVEATS

       This does not propagate properly across perl invocations like local::lib's stuff does. It
       can't. It's only a module import, so it only affects the specific perl VM instance in
       which you load and import() it.

       If you want to cascade it across invocations, you can set the PERL5OPT environment
       variable to '-Mlib::core::only' and it'll sort of work. But be aware that taint mode
       ignores this, so some modules' build and test code probably will as well.

       You also need to be aware that perl's command line options are not processed in order - -I
       options take effect before -M options, so

         perl -Mlib::core::only -Ilib

       is unlike to do what you want - it's exactly equivalent to:

         perl -Mlib::core::only

       If you want to combine a core-only @INC with additional paths, you need to add the
       additional paths using -M options and the lib module:

         perl -Mlib::core::only -Mlib=lib

         # or if you're trying to test compiled code:

         perl -Mlib::core::only -Mblib

       For more information on the impossibility of sanely propagating this across module builds
       without help from the build program, see
       <http://www.shadowcat.co.uk/blog/matt-s-trout/tainted-love> - and for ways to achieve the
       old --self-contained feature's results, look at App::FatPacker's tree function, and at
       App::cpanminus's --local-lib-contained feature.

AUTHOR

       Matt S. Trout <mst@shadowcat.co.uk>

LICENSE

       This library is free software under the same terms as perl itself.

COPYRIGHT

       (c) 2010 the lib::core::only "AUTHOR" as specified above.