--- Enters interactive debug mode, line with only "cont" terminates.
function debug()
--- Returns current hook function, hook mask, hook count.
function gethook()
--- Returns table with information about a function.
function getinfo(function [, what])
--- Returns name and value of local variable with index local at stack level.
function getlocal(level, local)
--- Returns name and value of upvalue with index up of function func.
function getupvalue(func, up)
--- Sets given function as a hook, mask="[crl]".
function sethook(hook, mask [, count])
--- Sets local variable with index local at stack level with value.
function setlocal(level, local, value)
--- Sets upvalue with index up of function func with value.
function setupvalue(func, up, value)
--- Returns a string with a traceback of the call stack.
function traceback([message])