Tue Jan 29 13:55:23 CET 2013

Why not simply OO then? - part II

DSP is about loops over grid, but the key insight is that the time
loop is different than the space loops:

- it is open
- it is a-symmetric
- it has a lot of associated "accumulator" state

Hiding the time loop and loop state from the view of the programmer
however creates an abstract view: at the level of streams, the
language is completely functional: there is no mention of state.
Operations are proper maps from streams to streams.

This is distinctly different from the OO approach where the time loop
is explicit (because it is open), and while state variables might be
abstracted, the fact that there is state is clearly visible through
the class/instance distinction.