"...fairly simple teaching framework."
Yes, is much more faster to code in pure Perl, specially if your main purpose is to make a flexible NN. But I saw that even for simple problems a NN needs speed, since if we build wrong the NN configurations for the target problem it will use a lot of CPU and time in the learning fase. Even a simple "tic tac toe" game, that I have used as a 1st real test for NNEasy, uses a lot of time to learn a big amount of inputs, so I started to add the XS support what make possible to learn fast the inputs and really play. In other words, NN always use a lot of CPU, so we can't run way from the C codes. About Class::HPLOO, for me is the fastest way to add the C support for the functions that really need that.
Graciliano M. P.
"Creativity is the expression of liberty".