lib::core::only(3) User Contributed Perl Documentation lib::core::only(3)NAMElib::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
DESCRIPTIONlib::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
<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.
perl v5.14.2 2011-02-18 lib::core::only(3)
