Module::Load
- NAME
- SYNOPSIS
- DESCRIPTION
- FUNCTIONS
- Rules
- IMPORTS THE FUNCTIONS
- Caveats
- ACKNOWLEDGEMENTS
- BUG REPORTS
- AUTHOR
- COPYRIGHT
NAME
Module::Load - runtime require of both modules and files
SYNOPSIS
use Module::Load; my $module = 'Data::Dumper'; load Data::Dumper; # loads that module, but not import any functions # -> cannot use 'Dumper' function load 'Data::Dumper'; # ditto load $module # tritto autoload Data::Dumper; # loads that module and imports the default functions # -> can use 'Dumper' function my $script = 'some/script.pl' load $script; load 'some/script.pl'; # use quotes because of punctuations load thing; # try 'thing' first, then 'thing.pm' load CGI, ':all'; # like 'use CGI qw[:standard]'
DESCRIPTION
Module::Load
eliminates the need to know whether you are trying to require either a file or a module.
If you consult perldoc -f require
you will see that require
will behave differently when given a bareword or a string.
In the case of a string, require
assumes you are wanting to load a file. But in the case of a bareword, it assumes you mean a module.
This gives nasty overhead when you are trying to dynamically require modules at runtime, since you will need to change the module notation (Acme::Comment
) to a file notation fitting the particular platform you are on.
Module::Load
eliminates the need for this overhead and will just DWYM.
Difference between load
and autoload
Module::Load
imports the two functions - load
and autoload
autoload
imports the default functions automatically, but load
do not import any functions.
autoload
is usable under BEGIN{};
.
Both the functions can import the functions that are specified.
Following codes are same.
load File::Spec::Functions, qw/splitpath/; autoload File::Spec::Functions, qw/splitpath/;
FUNCTIONS
-
load
Loads a specified module.
See Rules for detailed loading rule.
-
autoload
Loads a specified module and imports the default functions.
Except importing the functions, 'autoload' is same as 'load'.
-
load_remote
Loads a specified module to the specified package.
use Module::Load 'load_remote'; my $pkg = 'Other::Package'; load_remote $pkg, 'Data::Dumper'; # load a module to 'Other::Package' # but do not import 'Dumper' function
A module for loading must be quoted.
Except specifing the package and quoting module name, 'load_remote' is same as 'load'.
-
autoload_remote
Loads a specified module and imports the default functions to the specified package.
use Module::Load 'autoload_remote'; my $pkg = 'Other::Package'; autoload_remote $pkg, 'Data::Dumper'; # load a module to 'Other::Package' # and imports 'Dumper' function
A module for loading must be quoted.
Except specifing the package and quoting module name, 'autoload_remote' is same as 'load_remote'.
Rules
All functions have the following rules to decide what it thinks you want:
-
If the argument has any characters in it other than those matching
\w
,:
or'
, it must be a file -
If the argument matches only
[\w:']
, it must be a module -
If the argument matches only
\w
, it could either be a module or a file. We will try to findfile.pm
first in@INC
and if that fails, we will try to findfile
in @INC. If both fail, we die with the respective error messages.
IMPORTS THE FUNCTIONS
'load' and 'autoload' are imported by default, but 'load_remote' and 'autoload_remote' are not imported.
To use 'load_remote' or 'autoload_remote', specify at 'use'.
-
"load","autoload","load_remote","autoload_remote"
Imports the selected functions.
# imports 'load' and 'autoload' (default) use Module::Load; # imports 'autoload' only use Module::Load 'autoload'; # imports 'autoload' and 'autoload_remote', but don't import 'load'; use Module::Load qw/autoload autoload_remote/;
-
'all'
Imports all the functions.
use Module::Load 'all'; # imports load, autoload, load_remote, autoload_remote
-
'','none',undef
Not import any functions (
load
andautoload
are not imported).use Module::Load ''; use Module::Load 'none'; use Module::Load undef;
Caveats
Because of a bug in perl (#19213), at least in version 5.6.1, we have to hardcode the path separator for a require on Win32 to be /
, like on Unix rather than the Win32 \
. Otherwise perl will not read its own %INC accurately double load files if they are required again, or in the worst case, core dump.
Module::Load
cannot do implicit imports, only explicit imports. (in other words, you always have to specify explicitly what you wish to import from a module, even if the functions are in that modules' @EXPORT
)
ACKNOWLEDGEMENTS
Thanks to Jonas B. Nielsen for making explicit imports work.
BUG REPORTS
Please report bugs or other issues to <[email protected]<gt>.
AUTHOR
This module by Jos Boumans <[email protected]>.
COPYRIGHT
This library is free software; you may redistribute and/or modify it under the same terms as Perl itself.
© 1993–2016 Larry Wall and others
Licensed under the GNU General Public License version 1 or later, or the Artistic License.
The Perl logo is a trademark of the Perl Foundation.
https://perldoc.perl.org/5.22.0/Module/Load.html