Some coding style questions:
in reply to mapcar -- map for more than one list
- Why do you use if (! ...) and not unless (...)?
- Why do you use require and not use?
- Why didn't you extract out the common parts of mapcar() and mapcaru() and call some other function? Was it speed issues? (This would indicate we need a #define in Perl...)
We are the carpenters and bricklayers of the Information Age.
Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.