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C macros in Python.

Grant Griffin not.this at seebelow.org
Wed Oct 18 13:32:00 EDT 2000 
In article <slrn8updfp.ero.quinn at zloty.ugcs.caltech.edu>,
quinn at zloty.ugcs.caltech.edu says...
>
>On Tue, 17 Oct 2000 11:30:35 +0100, Burkhard Kloss <bk at xk7.com> wrote:
>>> On a different, but related, topic...I sometimes miss C's #define
>>> macro.  There doesn't seem to be any similar thing in Python capable of
>>> creating identifiers which are 1) constant, that is, "read only", and 2)
>>> truly global in scope.
>>How about defining a function that returns the value?  that would make it
>>nicely read-only.
>>
>>define pi(): return 3.14....
>
>pi = 3
>
>will defeat that nicely.

(BTW, here's a "Python Moment" if ever there was one: I realized awhile back
that tuples are essentially read-only lists.)

>If you want something to be constant in python, don't reassign it.  Not that
>hard, now is it? :)  And if you want something "truly global" you could shove
>it into __builtins__, which is great not only for confusing other people but
>also increasing job security.  And that's why you want globals in the first
>place, right? :)

In my own case, I just would like to have the global constants:

   True = 1
   False = 0

>Or, you could just run all your python scripts through cpp.

1 (meaning: "True" <wink>), but that sounds like more trouble than it's worth.

those-who-would-like-"True"-and-"False"-get-"None"-ly y'rs,

=g2

_____________________________________________________________________

Grant R. Griffin                                       g2 at dspguru.com
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