# Returns argument `arg_name` as a Bool or `null` if not found or not a boolean.
	#
	# NOTE: Prioritizes POST before GET
	fun bool_arg(arg_name: String): nullable Bool do
		if not all_args.has_key(arg_name) then return null
		var i = all_args[arg_name]
		if i == "true" then return true
		if i == "false" then return false
		return null
	end