NAME
lib::noop - no-op loading of some modules
VERSION
This document describes version 0.006 of lib::noop (from Perl
distribution lib-noop), released on 2021-06-07.
SYNOPSIS
use lib::noop qw(Foo::Bar Baz);
use Foo::Bar; # now a no-op
use Qux; # load as usual
DESCRIPTION
Given a list of module names, it will make subsequent loading of those
modules a no-op. It works by installing a require hook in @INC that
looks for the specified modules to be no-op'ed and return "1;" as the
source code for those modules.
This makes loading a no-op'ed module a success, even though the module
does not exist on the filesystem. And the %INC entry for the module will
be added, making subsequent loading of the same module a no-op too
because Perl's require will see that the entry for the module in %INC
already exists.
But, since the loading is a no-op operation, no code other than "1;" is
executed and if the original module contains function or package
variable definition, they will not be defined.
This pragma can be used e.g. for testing.
To cancel the effect of lib::noop, you can unimport it. If you then want
to actually load a module that has been no-op'ed, you have to delete its
%INC entry first:
use lib::noop qw(Data::Dumper);
use Data::Dumper;
# this code will die because Data::Dumper::Dumper is not defined
BEGIN { print Data::Dumper::Dumper([1,2,3]) }
no lib::noop;
BEGIN { delete $INC{"Data/Dumper.pm"} }
use Data::Dumper;
# this code now runs ok
BEGIN { print Data::Dumper::Dumper([1,2,3]) }
CONTRIBUTOR
perlancar (on netbook-dell-xps13) <perlancar@gmail.com>
HOMEPAGE
Please visit the project's homepage at
<https://metacpan.org/release/lib-noop>.
SOURCE
Source repository is at <https://github.com/perlancar/perl-lib-noop>.
BUGS
Please report any bugs or feature requests on the bugtracker website
<https://rt.cpan.org/Public/Dist/Display.html?Name=lib-noop>
When submitting a bug or request, please include a test-file or a patch
to an existing test-file that illustrates the bug or desired feature.
SEE ALSO
lib::noop::all
lib::noop::except
lib::noop::all_missing
AUTHOR
perlancar <perlancar@cpan.org>
COPYRIGHT AND LICENSE
This software is copyright (c) 2021, 2016 by perlancar@cpan.org.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.