Listable Subvalues

Q: I am writing functions for translating graphics primitives. The following function translates a single line object.

However, if I have a list of lines it does not work.

What is the best solution?

A: You can map your function over the list of lines.

Adding a rule to f for the case of list arguments makes this mapping operation automatic.

David Park (djmp@earthlink.net) provides an alternative solution: define as Function. The third argument to Function is a list of attributes for the purpose of evaluation.

Functions for transforming objects in 2 and 3 dimensions are defined in [1] with the packages available at [2].