NAME

       Dancer::ModuleLoader - dynamic module loading helpers for Dancer core components

VERSION

       version 1.3513

SYNOPSIS

       Taken directly from Dancer::Template::TemplateToolkit (which is core):

           die "Template is needed by Dancer::Template::TemplateToolkit"
             unless Dancer::ModuleLoader->load('Template');

           # we now have Template loaded

DESCRIPTION

       Sometimes in Dancer core we need to use modules, but we don't want to declare them all in
       advance in compile-time. These could be because the specific modules provide extra
       features which depend on code that isn't (and shouldn't) be in core, or perhaps because we
       only want these components loaded in lazy style, saving loading time a bit. For example,
       why load Template (which isn't required by Dancer) when you don't use
       Dancer::Template::TemplateToolkit?

       To do such things takes a bit of code for localizing $@ and "eval"ing. That code has been
       refactored into this module to help Dancer core developers.

       Please only use this for Dancer core modules. If you're writing an external Dancer module
       (Dancer::Template::Tiny, Dancer::Session::Cookie, etc.), please simply ""use
       ModuleYouNeed"" in your code and don't use this module.

METHODS/SUBROUTINES

   load
       Runs something like ""use ModuleYouNeed"" at runtime.

           use Dancer::ModuleLoader;
           ...
           Dancer::ModuleLoader->load('Something')
               or die "Couldn't load Something\n";

           # load version 5.0 or more
           Dancer::ModuleLoader->load('Something', '5.0')
               or die "Couldn't load Something\n";

           # load version 5.0 or more
           my ($res, $error) = Dancer::ModuleLoader->load('Something', '5.0');
           $res or die "Couldn't load Something : '$error'\n";

       Takes in arguments the module name, and optionally the minimum version number required.

       In scalar context, returns 1 if successful, 0 if not.  In list context, returns 1 if
       successful, "(0, "error message")" if not.

       If you need to give argument to the loading module, please use the method
       "load_with_params"

   require
       Runs a ""require ModuleYouNeed"".

           use Dancer::ModuleLoader;
           ...
           Dancer::ModuleLoader->require('Something')
               or die "Couldn't require Something\n";
           my ($res, $error) = Dancer::ModuleLoader->require('Something');
           $res or die "Couldn't require Something : '$error'\n";

       If you are unsure what you need ("require" or "load"), learn the differences between
       "require" and "use".

       Takes in arguments the module name.

       In scalar context, returns 1 if successful, 0 if not.  In list context, returns 1 if
       successful, "(0, "error message")" if not.

   load_with_params
       Runs a ""use ModuleYouNeed qw(param1 param2 ...)"".

           use Dancer::ModuleLoader;
           ...
           Dancer::ModuleLoader->load_with_params('Something', qw(param1 param2) )
               or die "Couldn't load Something with param1 and param2\n";

           my ($res, $error) = Dancer::ModuleLoader->load_with_params('Something', @params);
           $res or die "Couldn't load Something with @params: '$error'\n";

       Takes in arguments the module name, and optionally parameters to pass to the import
       internal method.

       In scalar context, returns 1 if successful, 0 if not.  In list context, returns 1 if
       successful, "(0, "error message")" if not.

   use_lib
       Runs a ""use lib qw(path1 path2)"" at run time instead of compile time.

           use Dancer::ModuleLoader;
           ...
           Dancer::ModuleLoader->use_lib('path1', @other_paths)
               or die "Couldn't perform use lib\n";

           my ($res, $error) = Dancer::ModuleLoader->use_lib('path1', @other_paths);
           $res or die "Couldn't perform use lib : '$error'\n";

       Takes in arguments a list of path to be prepended to @INC, in a similar way than "use
       lib". However, this is performed at run time, so the list of paths can be generated and
       dynamic.

       In scalar context, returns 1 if successful, 0 if not.  In list context, returns 1 if
       successful, "(0, "error message")" if not.

   class_from_setting
       Given a setting in Dancer::Config, composes the class it should be.

       This is the function that translates:

           # in config.yaml
           template: "template_toolkit"

       To the class:

           Dancer::Template::TemplateToolkit

       Example:

           use Dancer::ModuleLoader;
           my $class = Dancer::ModuleLoader->class_from_setting(
               'Dancer::Template' => 'template_toolkit',
           );

           # $class == 'Dancer::Template::TemplateToolkit

           $class = Dancer::ModuleLoader->class_from_setting(
               'Dancer::Template' => 'tiny',
           );

           # class == 'Dancer::Template::Tiny

SEE ALSO

       Module::Load, Module::New::Loader

AUTHOR

       Dancer Core Developers

COPYRIGHT AND LICENSE

       This software is copyright (c) 2010 by Alexis Sukrieh.

       This is free software; you can redistribute it and/or modify it under the same terms as
       the Perl 5 programming language system itself.