perl-Devel-Hide

Given a list of Perl modules/filenames, this module makes 'require' and
'use' statements fail (no matter the specified files/modules are installed
or not).
They die with a message like:
Can't locate Module/ToHide.pm in @INC (hidden)


The original intent of this module is to allow Perl developers to test for
alternative behavior when some modules are not available. In a Perl
installation, where many modules are already installed, there is a chance
to screw things up because you take for granted things that may not be
there in other machines.
For example, to test if your distribution does the right thing when a
module is missing, you can do
perl -MDevel::Hide=Test::Pod Makefile.PL


forcing 'Test::Pod' to not be found (whether it is installed or not).
Another use case is to force a module which can choose between two
requisites to use the one which is not the default. For example,
'XML::Simple' needs a parser module and may use 'XML::Parser' or 'XML::SAX'
(preferring the latter). If you have both of them installed, it will always
try 'XML::SAX'. But you can say:
perl -MDevel::Hide=XML::SAX script_which_uses_xml_simple.pl


NOTE. This module does not use Carp. As said before, denial dies.
This module is pretty trivial. It uses a code reference in @INC to get rid
of specific modules during require - denying they can be successfully
loaded and stopping the search before they have a chance to be found.
There are three alternative ways to include modules in the hidden list:

import()

this is probably the most commonly used method, called automagically when
you do this:
use Devel::Hide qw(Foo Bar::Baz);


or
perl -MDevel::Hide=...



setting @Devel::Hide::HIDDEN

environment variable DEVEL_HIDE_PM


both of these two only support 'global' hiding, whereas 'import()' supports
lexical hiding as well.
Optionally, you can provide some arguments before the list of modules:

-from:children

propagate the list of hidden modules to your process' child processes. This
works by populating 'PERL5OPT', and is incompatible with Taint mode, as
explained in perlrun. Of course, this is unnecessary if your child
processes are just forks of the current one.

-lexically

This is only available on perl 5.10.0 and later. It is a fatal error to try
to use it on an older perl.
Everything following this will only have effect until the end of the
current scope. Yes, that includes '-quiet'.

-quiet

suppresses diagnostic output. You will still get told about errors. This is
passed to child processes if -from:children is in effect.

          

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License: Artistic-1.0 OR GPL-1.0-or-later
URL: https://metacpan.org/release/Devel-Hide