Re: hackerlab fsplay.[ch] status

Tom Lord <lord-1tv/[email protected]> Sun, 2 May 2004 09:04:23 -0700 (PDT)
Newsgroups gmane.lisp.scheme.pika.devel
Message-ID <[email protected]>
    > From: Andreas Rottmann <[email protected]>

    > I've started porting the GLib memchunk implementationn to
    > hackerlab. I'm using the functional splay tree (fsplay.[hc])
    > implementation for the tree bookkeeping, and have fixed (one-line
    > change) a quite obvious bug in fsplay_raise() in the process[0]. 

    > Given that fsplay_raise() never worked correctly, what is the status
    > of the fsplay code -- is there anything that uses it so far? I'm now
    > experiencing an endless loop inside fsplay_raise()...


Nothing currently uses fsplay.

I started work on it because I was getting tired of having not yet
started work on it :-)

It's unsurprising that there are bugs --- tests aren't even written
yet.

The trivial bug aside: I would guess that the infinite loop you are
seeing is when you are trying to raise an element that isn't present
in the tree.  (Note the the bottom of the long comment in the
"zig-zig" case.)

I do recall realizing at one point (while away-from-keyboard) that
there was a bug there but I don't recall specifically what it was.

-t