Why doesn't default property invoke for if statement?

Andreas Kostyrka andreas at mtg.co.at
Sun Jan 6 18:54:15 CET 2002


On Wed, 12 Dec 2001 16:02:49 GMT
"Duffy O'Craven" <dufw1 at quinda.com> wrote:

> When using my component, I am hoping to avoid making script writing
> error-prone. So I want to require exactly the same expression for print as
> for anywhere else in the script. But I am also hoping that reference to an
> object, which in many contexts is just a boolean, can use the default
> binding id(0) aspect of COM. Unfortunately
> 
>      if  Trans.Status.Value:
>        print Trans.Status
> 
>      print "case 2",
>      if 0 != Trans.Status:
>        print Trans.Status
> 
>      print "case 3",
>      if Trans.Status:
>        print Trans.Status
> 
> prints
> case 2 0
> case 3 0
> 
> I think that        print Trans.Status
> invokes the default property of Status, which is Status.Value, but
> I think that        if  Trans.Status:
> does not.
Well, print applies str() to the object. Basically, 
you could change the if statement as follows:

if "0" != str(Trans.Status):
	...

Actually, I don't see a possibility to achieve your goal. (There might be
some possibilities, but for them I know not enough about Win32/COM ;) )

Andreas




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