Common in Lua, Ruby, Python. In fact, ruby gives _ a minor amount of special meaning to make it more convenient as a throw-away variable, e.g. it can be specifi

Common in Lua, Ruby, Python. In fact, ruby gives _ a minor amount of special meaning to make it more convenient as a throw-away variable, e.g. it can be specified multiple times in an argument list without an error and generates no warning if left unused.