[Python-ideas] Add list.join() please

Brendan Barnwell brenbarn at brenbarn.net
Tue Jan 29 21:58:54 EST 2019

On 2019-01-29 16:14, MRAB wrote:
> On 2019-01-29 23:38, Greg Ewing wrote:
>> Brendan Barnwell wrote:
>>>     Personally what I find is perverse is that .join is a method of
>>> strings but does NOT call str() on the items to be joined.
>> Neither do most other string methods:
>>   >>> s = "hovercraft"
>>   >>> s.count(42)
>> Traceback (most recent call last):
>>     File "<stdin>", line 1, in <module>
>> TypeError: Can't convert 'int' object to str implicitly
>> Why should join() be any different?
> And what if you don't want str, but instead repr, or ascii?

	Then you can still convert them yourself beforehand, and any 
stringifying that .join did would be a no-op.  If you want to call repr 
on all your stuff beforehand, great, then you'll get strings and you can 
join them just like anything else.  But you'll ADDITIONALLY be able to 
not pre-stringify them in a custom way, in which case they'll be 
stringified in the default way.

Brendan Barnwell
"Do not follow where the path may lead.  Go, instead, where there is no 
path, and leave a trail."
    --author unknown

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