"Ka-Ping Yee" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED]
On the consistency argument: sorted(somelist) calls copy(somelist).sort, not copy(somelist).__sort__. But I don't expect to see this change proposed. | Transition Plan | =============== | | Two additional transformations will be added to the 2to3 translation | tool [2]_: | | * Method definitions named ``next`` will be renamed to ``__next__``. Consistently renaming 'next' to '__next__', including at call sites, would be one thing... As explained below, you *must* translate at least non-call name lookups to not break programs. | * Explicit calls to the ``next`` method will be replaced with calls | to the built-in ``next`` function. For example, ``x.next()`` will | become ``next(x)``. But this is something else -- a de-optimization. One of the virtues, and as I recall, design purposes, of .next calls is to be fast. After the first call, execution jumps directly into the pre-existing stack frame. This change would interpose a regular old slow call process, thereby undoing this speedup (relative to the older .__getitem__ protocol). The next 'method' is uniquely intended to be called repeatedly, even billions of times, on the same instance, with the same args (none). So it should be as fast as possible. It is also useless for a large class of explicit uses. Explicit calls are usually done within a while loop. It is then fairly standard to factor out the attribute lookup with with 'xnext = x.next' or 'xnext = genx(args).next' before the loop and use the bound method within the loop. (I presume the for loop machinery does the same.) * So the translation tool must also change the name to '__next__' in such attribute lookups. Terry Jan Reedy _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
