cbsw

I don't think "lazy" is a problem in real code. They just annoys when in interactive shell which you just want to print their result. In fact python3 has changed a lot of list like data type or function to "lazy", zip(),dict.items() etc. IMO this helps a lot to reduce memory usage. Thus more efficient with functional programming

+ - * / even doesn't support multi-data. (+ 1 2 3) would be 3,stupid