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# Module::Load

Perl 5 version 22.0 documentation
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# Module::Load

- NAME
- SYNOPSIS
- DESCRIPTION
  - Difference between load and autoload
- 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 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@rt.cpan.org<gt>.

# AUTHOR

This module by Jos Boumans <kane@cpan.org>.

# COPYRIGHT

This library is free software; you may redistribute and/or modify it under the same terms as Perl itself.

Page index

- NAME
- SYNOPSIS
- DESCRIPTION
  - Difference between load and autoload
- FUNCTIONS
- Rules
- IMPORTS THE FUNCTIONS
- Caveats
- ACKNOWLEDGEMENTS
- BUG REPORTS
- AUTHOR
- COPYRIGHT