On 11/22/06, Guido van Rossum <[EMAIL PROTECTED]> wrote: > On 11/22/06, Jonathan LaCour <[EMAIL PROTECTED]> wrote: > > Phillip J. Eby wrote:
> > > In essence, interfaces turn libraries into "frameworks", but generic > > > functions turn frameworks into libraries. I didn't really discover > > > this until January of last year ... > > This is easily the most important part of the conversation, IMO, and I > > would hate for it to be missed. "Interfaces" in the Java universe are a > > hard contract that everyone has to agree upon up-front, ... you end up > > with is a world of many competing frameworks, none of which interoperate. > > ... something that seems a tad magical at first > > I have actually used generic functions (using RuleDispatch) in practice > > and find them to not only be hugely powerful, but much more pragmatic. > Sorry, but that was about as informative as a "+1" vote. I found it a bit more specific on two points: What I (mis?)read was: (1) PJE: Interfaces rely on buyin; they end up accidentally creating walled gardens. Generic Functions make fewer demands, so they start to work sooner, and integrate better. [The down side is that finding the relevant code -- or even being sure that it *is* is the relevant code, and isn't overridden elsewhere -- gets more difficult. -jJ] Jonathan: Phillip has written a lot of long messages; this one point is particularly important for the summary. It captures a (the?) key advantage of generic functions. (2) Generic Functions are harder to get your head around, but once you do, they're worth it. Phillip has been saying this already, but it matters that someone else has gotten to the point where they are useful and seem simple. Personally, I stand by my assessment that they can make metaclasses look straightforward -- but that is partly because metaclasses have had their roughest edges worn off already. (For example, they no longer require compiling a C class so odd that the pattern gets named after someone.) If GF explanations start to come from several different people, the same process should eventually simplify them. If that happened quickly enough, it would change the tradeoffs. -jJ _______________________________________________ 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
