This module is used to debug templates and other modules, and to help track down problems or incorrect usage.
dump(value)
Converts any value (except for functions) into a string representation. The string is formatted as Lua syntax, so you should be able to take the output of this function and insert it back into a Lua module. Tables are processed recursively. Tabs are converted into spaces.
highlight_dump(value)
Does the same as dump, except it adds Lua syntax highlighting, and tabs are preserved.
{{#invoke:debug|error|message}}
This function is invoked from templates, and simply triggers a script error with a message. This is useful if you want to trigger a script error but don't have the time or knowledge to convert a template to Lua.
track(key)
Convenience function which transcludes a tracking subtemplate. The key is a string or a list of strings: track("key") or track{ "key1", "key2", "key3", ... }.
Usually invocations of this functions should look like this: require('Module:debug').track(key). Loading this module on the spot instead of ahead of time may prevent unnecessary transclusion list overload.