[Python-Dev] timsort for jython

Tim Peters tim.one@comcast.net
Mon, 05 Aug 2002 13:53:42 -0400

[Barry, on  '' in 'xyz']
> Is the nothing part of the everything?

That's right, and if Python is a programming language for mystics that's
clearly the best answer <wink>.

> I'm not sure what the natural interpretation should be,

    s1 in s2

if and only if there exists an int i such that

    s2[i : i+len(s1)] == s1

is the acade^H^H^H^H^Hmystic meaning, and that's true of every i
in -sys.maxint .. sys.maxint when s1 is empty.

> but why would you ever want to know if '' is in somestring?

That's the practical rub indeed.  You never want to know that, so if you end
up asking it it's almost certainly a logic error in preceding code.

> Usually I think you'd only want to know if '' == somestring, so perhaps
> we should break the symmetry here.

That is the question.