> I would have thought that a better solution would be to specify a > minimal set of methods in an abstract superclass and write the > additional methods using that minimal set. > > The concrete string implementations would be descended from the > superclass and would still be able to override the additional methods > with more efficient code were desired, such as in the 'str' class.
This does sound better to me too! Devin On Sun, Sep 25, 2011 at 8:47 PM, MRAB <pyt...@mrabarnett.plus.com> wrote: > On 26/09/2011 01:23, Devin Jeanpierre wrote: >>> >>> Why does it suck? >> >> The gist of what I was saying is that it's possible to define >> functions that do this "generically" so that one implementation of >> zfill can work with multiple implementations of strings. Having to >> reimplement every time when one implementation would do is bothersome >> and generally isn't done unless it has to be (thus why mmap lacks a >> zfill method). Having to do more work than necessary "sucks", as does >> having partial str implementations that don't do everything str does. >> >> Ideally, I would claim that if some interface will have multiple >> implementations, it should have as few methods as possible to make >> implementation as easy as possible, and move as much as possible >> _away_ from methods and into functions that work with arbitrary >> implementations of the interface. This minimizes the amount of work >> that must be done for implementors and thus makes life better. >> > [snip] > I would have thought that a better solution would be to specify a > minimal set of methods in an abstract superclass and write the > additional methods using that minimal set. > > The concrete string implementations would be descended from the > superclass and would still be able to override the additional methods > with more efficient code were desired, such as in the 'str' class. > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
