Dancer::ModuleLoader(3User Contributed Perl DocumentatiDancer::ModuleLoader(3)NAMEDancer::ModuleLoader - dynamic module loading helpers for Dancer core
components
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 $@ and "eval"ing.
That code has been refactored into this module to help Dancer core
developers.
Please only use this for Dancer core modules. If you're writing an
external Dancer module (Dancer::Template::Tiny,
Dancer::Session::Cookie, etc.), please simply ""use ModuleYouNeed"" in
your code and don't use this module.
METHODS/SUBROUTINES
load
Runs a ""use ModuleYouNeed"".
use Dancer::ModuleLoader;
...
Dancer::ModuleLoader->load('Something')
or die "Couldn't load Something\n";
# load version 5.0 or more
Dancer::ModuleLoader->load('Something', '5.0')
or die "Couldn't load Something\n";
# load version 5.0 or more
my ($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 argumentto 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('Something', qw(param1 param2) )
or die "Couldn't load Something\n";
my ($res, $error) = Dancer::ModuleLoader->load('Something', @params);
$res or die "Couldn't load Something : '$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
AUTHOR
Alexis Sukrieh
LICENSE AND COPYRIGHT
Copyright 2009-2010 Alexis Sukrieh.
This program is free software; you can redistribute it and/or modify it
under the terms of either: the GNU General Public License as published
by the Free Software Foundation; or the Artistic License.
See http://dev.perl.org/licenses/ for more information.
perl v5.14.1 2011-06-15 Dancer::ModuleLoader(3)