Re: Hwy doesn't len(None) return zero ?

[Dave Angel]

Stephen Hansen wrote:
On 6/30/10 11:39 AM, Stef Mientki wrote:
  hello,
I've lot of functions that returns their result in some kind of tuple /
list / array,
and if there is no result, these functions return None.
Now I'm often what to do something if I've more than 1 element in the
result.
So I test:

if len ( Result ) > 1 :

But to prevent exceptions, i've to write ( I often forget)
if Result and ( len ( Result ) > 1 ) :

Just do:

   if Result:

You don't have to do a length check > 1; because if Result has a 
length of 0, it'll be false too. So the above check will catch both 
None, and empty sequences.
<snip>
Look closer:  the OP wanted   len(Result) > 1  not   len(Result) > 0.  
For that, you need two checks, for example, as for example:
    if Result and (len(Result)>1):

.
DaveA
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