Billy Mays wrote:
On 07/25/2011 10:16 AM, Archard Lias wrote:
On Jul 25, 2:03 pm, Ian Collins<ian-n...@hotmail.com> wrote:
On 07/26/11 12:00 AM, Archard Lias wrote:
Still I dont get how I am supposed to understand the pipe and its task/
idea/influece on control flow, of:
return<statement> |<statement>
??
It's simply a bitwise OR.
Yes, but how does it get determined, which one actually gets returned?
The return statement returns a single value from a function context. The
pipe operator takes 2 values and bitwise ORs* them together. That
result is then returned to the caller.
Just for completeness, if the actual line had been
return <statement1> or <statement2>
then Python would compute <statement1>, and if its boolean value was
True would return the computation of <statement1>, otherwise it would
compute <statement2> and return that. When 'or' is used, the first
truthy* item is return, or the last falsey* item if none evaluate to True.
--> None or 2 or 0
2
--> None or 2 or 3
2
--> None or [] or 0
0
With 'and', the first falsey item is returned, unless all the items are
truthy in which case the last item is returned:
--> 2 and 3
3
--> 2 and 0 and 9
0
Hope this helps.
~Ethan~
* 'truthy' = bool(some expression or object) == True
* 'falsey' = bool(some expression or object) == False
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