On 2016-09-15 18:28, Michael Heerdegen wrote:
> Yes, more or less.  And I want to get an idea of how often "sometimes"
> is in the use cases where you want the negative indexes.

Emacs currently doesn't stream-based process filters, but they could be very nice; right now I'm not aware of a way to delay invocations of filter functions, so if you want to page through the output of a filter little by little you must still consume all of it and put it in a buffer.

Clément.