NAME
Poet::Import -- Import Poet quick vars and utilities
SYNOPSIS
# In a script...
use Poet::Script qw($conf $poet $log :file);
# In a module...
use Poet qw($conf $poet $log :file);
DESCRIPTION
Poet makes it easy to import certain variables (known as "quick vars") and utility sets into any script or module in your environment.
In a script:
use Poet::Script qw(...);
and in a module:
use Poet qw(...);
where ...
contains one or more quick var names (e.g. $conf
, $poet
) and/or utility tags (e.g. :file
, :web
).
(Note that use Poet::Script
is also necessary for initializing the environment, even if you don't care to import anything, whereas use Poet
has no effect other than importing.)
QUICK VARS
Here is the built-in list of quick vars you can import. Some of the variables are singletons, and some of them are specific to each package they are imported into.
- $poet
-
The global environment object, provided by Poet::Environment. This provides information such as the root directory and paths to subdirectories.
For backward compatibility this is also available as
$env
. - $conf
-
The global configuration object, provided by Poet::Conf.
- $cache
-
The cache for the current package, provided by Poet::Cache.
- $log
-
The logger for the current package, provided by Poet::Log.
UTILITIES
Default utilities
The utilities in Poet::Util::Debug are always imported, with no tag necessary.
:file
This tag imports all the utilities in Poet::Util::File.
:web
This tag imports all the utilities in Poet::Util::Web. It is automatically included in all Mason components.
MASON COMPONENTS
Every Mason component automatically gets this on top:
use Poet qw($conf $poet :web);
$m->cache
and $m->log
will get you the cache and log objects for a particular Mason component.
CUSTOMIZING
Adding variables
To add your own variable, define a method called provide_var_varname in MyApp::Import
. For example to add a variable $dbh
:
package MyApp::Import;
use Poet::Moose;
extends 'Poet::Import';
method provide_var_dbh ($caller) {
# Generate and return a dbh.
# $caller is the package importing the variable.
# $poet is the current Poet environment.
}
provide_dbh
can return a single global value, or a dynamic value depending on $caller
.
Now your scripts and libraries can do
use Poet::Script qw($dbh);
use Poet qw($dbh);
Adding utility tags
To add your own utility tag, define a class MyApp::Util::Mytagname
that exports a set of functions via the ':all' tag. For example:
package MyApp::Util::Hash;
use Hash::Util qw(hash_seed all_keys);
use Hash::MoreUtils qw(slice slice_def slice_exists);
our @EXPORT_OK = qw(hash_seed all_keys slice slice_def slice_exists);
our %EXPORT_TAGS = ( 'all' => \@EXPORT_OK );
1;
Now your scripts and libraries can do
use Poet::Script qw(:hash);
use Poet qw(:hash);
SEE ALSO
AUTHOR
Jonathan Swartz <swartz@pobox.com>
COPYRIGHT AND LICENSE
This software is copyright (c) 2012 by Jonathan Swartz.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.