[Tutor] why can't I find a function that givesme the sign of aninteger?

Rinzwind w.damen at gmail.com
Fri Jan 27 11:36:29 CET 2006

On 1/27/06, Alan Gauld <alan.gauld at freenet.co.uk> wrote:
> Orri,
> > Eh you mean to say that in next Python versions someone could decide
> > to change cmp(x,0) to another meaning? I bet my countryman (I'm from
> > Holland too ;-) ) will veto that! Or else I'll pay him a visit :D
> Its not another meaning, its the current meaning.
> Kent is just pointing out that while the default cmp currently
> returns -1,0,1
> there is nothing to stop a user defined cmp fom returning any negative or
> positive number instead of -1,1. And cmp() calls any user defined cmp
> under the hood.
> In theory the standard cmp could be changed in future although its
> unlikely..
> So while it is a nice trick it cannot be relied upon since it depends on a
> detail of implementation. In practice I suspect you are fairly safe :-)
> Alan G


Well I needed it to reflect -, 0 or + anyways so I should be safe. I
needed it to find out the direction of a chessmove so pawns could not
walk back and with that and the MIN and the MAX function I could do
with 1 for+while loops per direction (hor, vert or diag).

Oh, I am now on 32 hours of coding and started with 0 knowledge of
Python, PIL and/or Pygame and the 1st release should be out soon :-)
Just need to fix castling, promotion and en passant and I'm done! I

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