[Python-ideas] Allow function to return multiple values

[Mikhail V]

On 26 June 2017 at 01:14, rymg19 at gmail.com <rymg19 at gmail.com> wrote:
> IIRC I'm pretty sure the OP just didn't know about the existence of tuple
> unpacking and the ability to use that to return multiple values.
>

Can be so, though it was not quite clear. The original OP's
example function included same variables as input and output
and the phrasing "I noticed that this actually returns a tuple of the values
which I did not want in the first place" actually can indicate that my
theory can be also valid.

And it reminded me times starting with Python and  wondering
why I can't simply write something like:

def move(x,y):
    x = x + 10
    y = y + 20
move(x,y)

Instead of this:

def move(x,y):
    x1 = x + 10
    y1 = y + 20
    return x1,y1
x,y = move(x,y)


So probably there was some corellation with this and OP's
ideas, IDK.






> On Jun 25, 2017 at 6:09 PM, <Mikhail V> wrote:
>
> joannah nanjekye wrote:
>
>
>
>
>
>> [...]
>
>>
>
>>Today I was writing an example snippet for the book and needed to write a
>
>>function that returns two values something like this:
>
>>
>
>>def return_multiplevalues(num1, num2):
>
>>     return num1, num2
>
>>
>
>> I noticed that this actually returns a tuple of the values which I did not
>
>>want in the first place.I wanted python to return two values in their own
>
>>types so I can work with them as they are but here I was stuck with working
>
>>around a tuple.
>
>
>
> It was quite puzzling at first what was the actual idea but probably I
>
> can guess why this question came up by you.
>
> It seems to me (I am just intuitively guessing that) that you were about to
>
> write a procedure which operates on global variables.
>
> If so you should use the keyword "global" for that.
>
> E.g. if you want to work with the variables defined in other
>
> part of the code you can simply do it:
>
>
>
> x = 0
>
> y = 0
>
> def move():
>
>     global x, y
>
>     x = x + 10
>
>     y = y + 20
>
> move()
>
> print (x,y)
>
>
>
> This function will change x and y (global variables in this case).
>
> Note that without the line with the "global" statement this will not work.
>
> Another typical usage is initialising variables inside a procedure:
>
>
>
> def init_coordinates():
>
>     global x,y
>
>     x=0
>
>     y=0
>
> init_coordinates()
>
> print (x,y)
>
>
>
>
>
> So for some reason it seemed to me that you are trying to do
>
> something like that.
>
>
>
>>My proposal is we provide a way of functions returning multiple values.
>
>>This has been implemented in languages like Go and I have found many cases
>
>>where I needed and used such a functionality. I wish for this convenience
>
>>in python so that I don't  have to suffer going around a tuple.
>
>
>
> So if using globals as in the above examples you certinly don't
>
> have to suffer going around a tuple.
>
>
>
>
>
>
>
> Mikhail
>
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