Example of how to wrap script entry points to be able to do custom error handling

errorhandler.lua

local function on_error(err)
	print("In custom error handler:", err)
	-- something went wrong, handle error here
	-- report to client health for instance
	-- print(debug.traceback())
	-- dump tables
end

local function do_something(a_number)
	-- if this check fails it will be caught by the error handler
	assert(type(a_number) == "number", "Expected a number")

	-- the below code would also fail and get caught by the error handler
	print(nil + "some string")

	-- and this
	error("Oops")
end

local function _init(self)
	-- do init stuff here
	do_something("sending a string when number is expected")
end

function init(self)
	-- you can't pass arguments to xpcall so we need to wrap the function
	-- we could do the same for on_input(), on_message(), update() and final()
	local ok, result = xpcall(function() _init(self) end, on_error)
end

init({})