[Tutor] mistaken about splitting expressions over lines

[Albert-Jan Roskam]

_______________________________
>From: eryksun <eryksun at gmail.com>
>To: Jim Mooney <cybervigilante at gmail.com> 
>Cc: tutor at python.org 
>Sent: Tuesday, June 25, 2013 2:14 PM
>Subject: Re: [Tutor] mistaken about splitting expressions over lines

<snip>

>
>    >>> a = ('this'  # this way
>    ...      ' string' ' is long') # is more flexible
>    >>> a
>    'this string is long'

 
I did something similar after having read http://docs.python.org/2/howto/doanddont.html, under "Using Backslash to Continue Statements".
 
But I always use + signs. I didn't know that omitting them also works. Is str.__add__ called then, too?
Isn't this a violation of the 'Explicit is better than implicit(ly concatenate strings)' principle?
>>> a = ('this' +
              ' string' +
              ' is long')
>>> a
'this string is long'