Introducing libbean
===================

libbean is a gobject-based plugins engine, and is targetted at giving every
application the chance to assume its own extensibility. It is currently used by
the CAFE application lapiz.

It takes its roots in the old lapiz plugins engine, and provides an extensive set
of features mirroring the desiderata of most of the applications providing an
extension framework.

Multiple extension points
-------------------------

One of the most frustrating limitations of the Lapiz plugins engine was that it
only allows extending a single class, called LapizPlugin. With libbean, this
limitation vanishes, and the application writer is now able to provide a set of
GInterfaces the plugin writer will be able to implement as his plugin requires.

On-demand programming language support
--------------------------------------

libbean comes with a set of supported languages (currently, C, Lua 5.1,
Python 2 and Python 3). Those languages are supported through “loaders” which
are loaded on demand. What it means is that you only pay for what you use: if
you have no Python plugin, the Python interpreter won't be loaded in memory.
Of course, the same goes for the C loader.

Damn simple to use (or at least we try hard)
--------------------------------------------

Adding support for libbean-enabled plugins in your own application is a matter
of minutes. You only have to create an instance of the plugins engine, and
call methods on the implementations of the various extension points. That's it,
no clock harmed.

A few hints on using libbean
============================

As always for the new projects, it can take some time to grasp all the
subtleties at first.

Plugins versus Extensions
-------------------------

Something that is going to puzzle most of the newcomers is the fact that the
libbean API talks about both plugins and extensions, two terms that are usually
used interchangeably, but who have very different meanings in libbean.

Let's try and give a definition of both of these words in this context:

- Plugin: In the context of libbean, a plugin is a logical package. It's what
  you will enable or disable from the UI, and at the end it is what the user
  will see. An example of plugin for lapiz would be the file browser plugin.

- Extension. An extension is an object which implements an interface
  associated to an extension point. There can be several extensions in a single
  plugin. Examples of extensions provided by the file browser plugin would be
  the configuration dialog, the left panel pane and a completion provider for
  file names.

Sample code
-----------

The libbean package contains a sample application called bean-demo, and sample
plugins written in C, Lua and Python.

The global idea is this one: you create a new BeanEngine instance and give it
the information needed for it to find your plugins. Then you load some plugins
(you can use the BeanCtkPluginManager for that purpose) and perform actions
through some BeanExtensions objects you can get from the engine.