On 22-Feb-06, at 9:28 PM, [EMAIL PROTECTED] wrote:On 21-Feb-06, at 11:21 AM, Almann T. Goo" <[EMAIL PROTECTED]> wrote:Why not just use a class?def incgen(start=0, inc=1) : class incrementer(object): a = start - inc def __call__(self): self.a += inc return self.a return incrementer()a = incgen(7, 5)for n in range(10): print a(),Because I think that this is a workaround for a concept that thelanguage doesn't support elegantly with its lexically nested scopes.IMO, you are emulating name rebinding in a closure by creating anobject to encapsulate the name you want to rebind--you don't need thisworkaround if you only need to access free variables in an enclosingscope. I provided a "lighter" example that didn't need a callableobject but could use any mutable such as a list.This kind of workaround is needed as soon as you want to re-bind aparent scope's name, except in the case when the parent scope is theglobal scope (since there is the "global" keyword to handle this). It's this dichotomy that concerns me, since it seems to be against theelegance of Python--at least in my opinion.It seems artificially limiting that enclosing scope name rebinds arenot provided for by the language especially since the behavior withthe global scope is not so. In a nutshell I am proposing a solutionto make nested lexical scopes to be orthogonal with the global scopeand removing a "wart," as Jeremy put it, in the language.-Almann--Almann T. Goo[EMAIL PROTECTED]If I may be so bold, couldn't this be addressed by introducing a "rebinding" operator? So the ' = ' operator would continue to create a new name in the current scope, and the (say) ' := ' operator would for an existing name to rebind. The two operators would highlight the special way Python handles variable / name assignment, which many newbies miss.(from someone who was surprised by this quirk of Python before: http://www.thescripts.com/forum/thread43418.html) -Brendan--Brendan SimonsSorry, this got hung up in my email outbox. I see the thread has touched on this idea in the meantime. So, yeah. Go team. Brendan--Brendan Simons___
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