Characters contain themselves?

[Sion Arrowsmith]

Graham  Fawcett <graham.fawcett at gmail.com> wrote:
>You could always use an "is-proper-subset-of" function, which is closer
>to the intent of your algorithm. Using Jamitzky's very clever infix
>recipe [1], you can even write it as an infix operator:
>
>#Jamitzky's infix-operator class, abbreviated
>class Infix:
> [ ... ]
>
># define our is-proper-subset operator...
>ips = Infix(lambda a, b: (a is not b) and (a in b))
>
>>>> print 'a' |ips| 'a'
>False
>>>> print 'a' |ips| 'abc'
>True

Unfortunately:

>>> print 'abc' |ips| 'abc'
False
>>> print 'a'+'bc' |ips| 'abc'
True

Which might not be what you want. On the other hand, it's a simple
fix:

>>> ips = Infix(lambda a, b: (a != b) and (a in b))
>>> print 'a' |ips| 'abc'
True

>>> print 'a'+'bc' |ips| 'abc'
False

>[1] http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/384122

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