Re: reading the C source of Emacs

[David Kastrup <dak@gnu.org>]

Oliver Scholz <alkibiades@gmx.de> writes:

> Thank you all for you advice. You helped to set me on the track. But
> it is indeed a rather difficult read for me. My head dizzles is still
> a bit dizzling.
> 
> Below are my very first steps in C: a version of `find-if' as a
> starter. I'd appreciate any comment. (Did I miss something important,
> for example?)
> 
> One thing that I noticed is that my `find-if' causes an infinite loop,
> when applied to a recursive (?) list, à la:

There are several tricks for dealing with recursive data structures.
One is to have two traversals active at the same time, where one
traversal progresses just at every second step.  If they should ever
catch up, you have encountered a loop in a data structure.

I doubt this would be worth the trouble: just make sure that C-g will
be able to abort your function should it get stuck.

-- 
David Kastrup, Kriemhildstr. 15, 44793 Bochum