UNIVERSAL::require - require() modules from a variable [deprecated]
# This only needs to be said once in your program.
require UNIVERSAL::require;
# Same as "require Some::Module"
my $module = 'Some::Module';
$module->require or die $@;
# Same as "use Some::Module"
BEGIN { $module->use or die $@ }
Before using this module, you should look at the alternatives,
some of which are listed in SEE ALSO below.
This module provides a safe mechanism for loading a module at runtime,
when you have the name of the module in a variable.
If you've ever had to do this...
eval "require $module";
to get around the bareword caveats on require(), this module is for
you. It creates a universal require() class method that will work
with every Perl module and its secure. So instead of doing some
arcane eval() work, you can do this:
$module->require;
It doesn't save you much typing, but it'll make a lot more sense to
someone who's not a ninth level Perl acolyte.
my $return_val = $module->require or die $@;
my $return_val = $module->require($version) or die $@;
This works exactly like Perl's require, except without the bareword
restriction, and it doesn't die. Since require() is placed in the
UNIVERSAL namespace, it will work on any module. You just have to
use UNIVERSAL::require somewhere in your code.
Should the module require fail, or not be a high enough $version, it
will simply return false and not die. The error will be in
$@ as well as $UNIVERSAL::require::ERROR.
$module->require or die $@;
my $require_return = $module->use or die $@;
my $require_return = $module->use(@imports) or die $@;
Like UNIVERSAL::require, this allows you to use a $module without
having to eval to work around the bareword requirement. It returns the
same as require.
Should either the require or the import fail it will return false. The
error will be in $@.
If possible, call this inside a BEGIN block to emulate a normal use
as closely as possible.
BEGIN { $module->use }
UNIVERSAL::require makes use of eval STRING. In previous versions
of UNIVERSAL::require it was discovered that one could craft a class
name which would result in code being executed. This hole has been
closed. The only variables now exposed to eval STRING are the
caller's package, filename and line which are not tainted.
UNIVERSAL::require is taint clean.
Copyright 2001, 2005 by Michael G Schwern <schwern@pobox.com>.
This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.
See http://www.perl.com/perl/misc/Artistic.html
Michael G Schwern <schwern@pobox.com>
Now maintained by Neil Bowers (NEILB).
the Module::Load manpage provides functions for loading code,
and importing functions.
It's actively maintained.
the Module::Runtime manpage provides a number of usesful functions
for require'ing and use'ing modules,
and associated operations.
the Mojo::Loader manpage is a class loader and plugin framework.
the Module::Loader manpage is a stand-alone module that was inspired
by Mojo::Loader.
There are many other modules that may be of interest on CPAN.
An old review of some of them can be read at
https://neilb.org/reviews/module-loading.html.
perlfunc/require.
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