Function passed as an argument returns none

[Denis McMahon]

On Wed, 01 Oct 2014 22:37:13 +0000, Shiva wrote:

> Hi,
> I am learning Python (version 3.4) strings.I have a function that takes
> in a parameter and prints it out as given below.
> 
> def donuts(count):
>   if count <= 5:
>     print('Number of donuts: ',count)
>   else:
>     print('Number of donuts: many') return
> 
> It works fine if I call donuts(5)
> 
> It returns:

No it doesn't

> we have 5 DN  (as expected)

It doesn't return anything, it prints something out.

Printing something out from within a function is not the same as 
returning something.

Consider the following::

def nonsense( something ):
    print( "something is", something )
    return ( 5, "elephants", { "monkey": "peanut", "baboon": 
             "banana", "numbers": ( 1, ), }, [ 1, 2, 3, 4, 5, 
             "mouse",( -6.34565e-35, 4.765213e84, ), ], 
             None, True, False, )

print( "nonsense( 10 ) is", nonsense( 10 ) )
print( "nonsense( None ) is", nonsense( None ) )
print( "nonsense( ( 5, \"donuts\", ) ) is", nonsense( ( 5, "donuts", ) ) )

The above code shows there is no automatic connection between data output 
carried out within a function and the value (if any) returned by that 
function.

-- 
Denis McMahon, denismfmcmahon at gmail.com