On 2008-02-01, Roger Miller <[EMAIL PROTECTED]> wrote: > On Jan 31, 11:48 am, Grant Edwards <[EMAIL PROTECTED]> wrote: >> I'm not sure what you're asking. AFAIK, the main reason that >> strings are immutable is so they can be used as dict keys. > > I think its more fundamental than that. If strings were mutable > you would be constantly worrying about whether changing a string > here might affect something there, or whether to write x = y or > x = copy.copy(y).
Sure. I don't think any of those considerations are fundamentally different than what we face now with lists, though, are they? Lists can be thought of as the mutable version of the tuple, and sets come in a pair with frozensets so you can get whichever flavor you need for your application. I'm all for the default string implementation being immutable, since it facilitations certain operations and avoids certain classes of problems, but it isn't obvious to me why there isn't a class of a different name, such as "mutablestring", for when one wants that. Even having just the += operator and slicing make modifications in place could be a win. I guess for complete symmetry, there should then be frozendicts as well, although I don't envision a lot of use for them at the moment. -- http://mail.python.org/mailman/listinfo/python-list
