Rob Williscroft wrote: > Frederic Rentsch wrote in news:mailman.1536.1162292996.11739.python- > [EMAIL PROTECTED] in comp.lang.python: > > >> Rob Williscroft wrote: >> >>> Frederic Rentsch wrote in news:mailman.1428.1162113628.11739.python- >>> [EMAIL PROTECTED] in comp.lang.python: >>> >>> >>> > > >>> def whatever( new_ms ): >>> class namespace( object ): >>> pass >>> scope = namespace() >>> >>> def inner(): >>> scope.mseconds = new_ms - s * 1000 >>> m, scope.seconds = divmod (s, 60) >>> h, scope.minutes = divmod (m, 60) >>> d, scope.hours = divmod (h, 24) >>> scope.weeks, scope.days = divmod (d, 7) >>> >>> >>> >> This is interesting. I am not too familiar with this way of using >> objects. Actually it isn't all that different from a list, because a >> list is also an object. But this way it's attribute names instead of >> list indexes which is certainly easier to work with. Very good! >> >> > > >>> In short I think an "outer" keyword (or whatever it gets called) >>> will just add another way of doing something I can already do, >>> and potentially makes further refactoring harder. >>> >>> >>> >> Here I'm lost. What's the advantage of this? It looks more convoluted. >> > > I'll agree that having to explicitly define a namespace class first > does add some convolution. > > But if you refer to having to prefix you "outer" variables with "scope." > then this would be the same as claiming that the explict use of self is > convoluted, which is a valid opinion, so fair enough, but I can't say > that I agree. > >
I didn't mean to call into question. I didn't understand the advantage of the added complexity of your second example over the first. > It should also be noted that although I have to declare and create a > scope object. My method doesn't require the attributes passed back from > the inner function be pre-declared, should I during coding realise > that I need to return another attribute I just assign it in the inner > function and use it in the outer function. I would count that as less > convoluted, YMMV. > That is certainly a very interesting aspect. > > >> And speaking of convoluted, what about efficiency? There is much talk >> of efficiency on this forum. I (crudely) benchmark your previous >> example approximately three times slower than a simple inner function >> taking and returning three parameters. It was actually the aspect of >> increased efficiency that prompted me to play with the idea of >> allowing direct outer writes. >> > > Did you have optimisation turned on ? > > No. I did a hundred thousand loops over each in IDLE using xrange. > As I see it there should be no reason an optimiser couldn't transform > my code into the same code we might expect from your "outer keyword" > example, as the scope object's type and attributes are all contained > within (thus known to) the outer function defenition. > > I doubt that very much. The 'outer' keyword would give me the choice between two alternatives. Such a choice can hardly be automated. > Wether CPython's optimiser does this or not, I don't know. > > >>> Thats -2 import-this points already. >>> >>> >>> >> Which ones are the two? >> > > Explicit is better than implicit. > There should be one-- and preferably only one --obvious way to do it. > > Rob. > Frederic -- http://mail.python.org/mailman/listinfo/python-list
