Re: TypeError expected in an augmented assignment

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From	Terry Reedy <tjreedy@udel.edu>
Subject	Re: TypeError expected in an augmented assignment
Date	Wed, 02 Jul 2014 22:57:49 -0400
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On 7/2/2014 10:39 PM, candide wrote:
> An hybrid list-tuple concatenation is not allowed
>
>>>> []+(1, 2)
> Traceback (most recent call last):
>    File "<stdin>", line 1, in <module>
> TypeError: can only concatenate list (not "tuple") to list
>>>>
>
>
>
> hence I was expecting (*) that the following code raises a TypeError :
>
>>>> x = []
>>>> x += (1, 2)
>>>> x
> [1, 2]
>>>>
>
>
> Any explanation ?
 >>> seq = [1,2]
 >>> seq.extend((3,4))
 >>> seq+= {5, 6}  # the order of extending is not determined
 >>> seq
[1, 2, 3, 4, 5, 6]
 >>>

-- 
Terry Jan Reedy

Thread

TypeError expected in an augmented assignment candide <c.candide@laposte.net> - 2014-07-02 19:39 -0700
  Re: TypeError expected in an augmented assignment Terry Reedy <tjreedy@udel.edu> - 2014-07-02 22:57 -0400
    Re: TypeError expected in an augmented assignment candide <c.candide@laposte.net> - 2014-07-03 00:51 -0700
      Re: TypeError expected in an augmented assignment Chris Angelico <rosuav@gmail.com> - 2014-07-03 18:36 +1000
        Re: TypeError expected in an augmented assignment candide <c.candide@laposte.net> - 2014-07-03 02:35 -0700
          Re: TypeError expected in an augmented assignment Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-07-03 13:43 +0100

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