9.1. Introduction

Aqualung is written in the C programming language, but if compiled with Lua support, embeds a Lua interpreter that can used by the user to change Aqualung's behavior or add custom functions without recompiling the program. Aqualung supports the following 5 types of extensions:

• Title Format
• Hooks
• Playlist Menu Commands
• Remote Commands
• Keybindings

The Lua extension file setting appears if Aqualung is compiled with Lua support. It allows you to choose a `.lua' file containing Lua code that implements any of the above extensions. You can type in the path to the file or click Browse to get a file chooser. The `.lua' file should be a valid Lua source code file.

If you change the Lua extension file setting in the options page, and accept the changes, Aqualung will close the existing Lua interpreter and create a new Lua intepreter. To close the existing Lua interpreter and immediately reopen it with the same extension file, use the Reload Lua interpreter setting. Note that whenever the Lua interpreter is closed, all Lua-internal state is lost.