Module::Load(3) User Contributed Perl Documentation Module::Load(3)
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:
o If the argument has any characters in it other than those matching
"\w", ":" or "'", it must be a file
o If the argument matches only "[\w:']", it must be a module
o If the argument matches only "\w", it could either be a module or a
file. We will try to find "file.pm" first in @INC and if that
fails, we will try to find "file" 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" and "autoload" 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 <bug-module-load AT rt.org<gt>.
AUTHOR
This module by Jos Boumans <kane AT cpan.org>.
COPYRIGHT
This library is free software; you may redistribute and/or modify it
under the same terms as Perl itself.
perl v5.26.3 2014-02-20 Module::Load(3)