Re: [Numpy-discussion] Numarray 0.5

[Peter V. <ve...@em...>]

> > I am not sure if this is a bug, or intended behaviour, but the possib=
ilty
> > to compare an array type object to 'Any' would be very useful for me.
>
> 'Any' grew up from the C-API,  rather than down from the Python design,
> so it's not very well thought out.  Right now,  it is a placeholder use=
d
> to mark arrays with undefined types and to indicate "no type constraint=
"
> in C API calls.  In normal contexts,   you can't make an array of type
> 'Any'.  I think there are two reasonable behaviors for comparisons with
> 'Any',  both used in C.   The first behavior is literal comparison; her=
e
> comparison to Any would generally return "not equal".  The second
> behavior is wild-card matching; here, comparison to Any would generally
> return "equal".   Which makes sense to you?  How do you want to use
> this?

I use 'Any' right now in C functions to indicate 'no type constraint'. Yo=
u=20
could use both literal comparison and wild-card matching behaviour for th=
at,=20
if you want to do this in Python, I think. But maybe one should not do su=
ch a=20
thing in Python by comparison to 'Any' at all.

Literal comparison is what I generally expect from Python objects, so any=
thing=20
else may just be confusing (at least to me). However, the name 'Any' does=
=20
suggest the wild-card matching behaviour.=20

Is there specific reason why you exposed 'Any' in python? Maybe it would =
be=20
better not to expose such a type object since it seems to be a 'special=20
case'. I am starting to think that my use for it at the Python level is n=
ot=20
appropiate. For instance, I could easily use 'None' instead, and I think =
I=20
will do that in the future.=20

You mentioned that 'Any' is really a C-API thing. Unless somebody has a g=
ood=20
use for it I would now actually say that it maybe should not be exposed a=
t=20
the Python API level at all...

Cheers, Peter
=20
--=20
Dr. Peter J. Verveer
Cell Biology and Cell Biophysics Programme
EMBL
Meyerhofstrasse 1
D-69117 Heidelberg
Germany
Tel. : +49 6221 387245
Fax  : +49 6221 387242
Email: Pet...@em...