why cannot assign to function call
Erik Max Francis
max at alcyone.com
Thu Jan 8 02:07:29 CET 2009
Terry Reedy wrote:
> Joe Strout wrote:
>> That's not necessarily true. If you have
>> a = "par" + "rot"
>> b = "parrot"
>> then, most likely (though it depends on how clever the compiler
>> optimizations are), there are two different string objects containing
>> the data "parrot".
> >>> a='par'+'rot'
> >>> b='parrot'
> >>> a is b
One exactly doesn't really say much. It's implementation dependent, and
depends on the length of the string:
>>> a = 'this is a much longer ' + 'parrot'
>>> b = 'this is a much longer parrot'
>>> a is b
In practice, tests like these are pretty much never useful. It's
completely implementation dependent when and under what circumstances
fundamental immutable objects are reused, and it's not useful anyway;
what you care about is whether two objects are equal or not, not whether
they're the same object through some optimization behind the scenes.
Erik Max Francis && max at alcyone.com && http://www.alcyone.com/max/
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