On Sat, Dec 6, 2008 at 1:33 PM, Carl Banks <[EMAIL PROTECTED]> wrote: > On Dec 5, 8:21 pm, "Daniel Fetchinson" <[EMAIL PROTECTED]> > wrote: >> Hi folks, >> >> The story of the explicit self in method definitions has been >> discussed to death and we all know it will stay. However, Guido >> himself acknowledged that an alternative syntax makes perfect sense >> and having both (old and new) in a future version of python is a >> possibility since it maintains backward compatibility. The alternative >> syntax will be syntactic sugar for the old one. This blog post of his >> is what I'm talking about: >> >> http://neopythonic.blogspot.com/2008/10/why-explicit-self-has-to-stay... >> >> The proposal is to allow this: >> >> class C: >> def self.method( arg ): >> self.value = arg >> return self.value >> >> instead of this: >> >> class C: >> def method( self, arg ): >> self.value = arg >> return self.value > > > > -1 > > I explained why deep in the thread but I'll elaborate more here. When > I see a def statement, I mentally equate that to an assigment to the > thing being def'ed. So for instance, when I see this: > > def <something>(): > > I think of it like this: > > <somthing> = <the defined function> > > > Thus, if I were to see a function definition like this > > def foo.bar(): return 1 > > I would think you were defining a function and assigning it to > foo.bar. IOW, it would be mostly equivalent to this: > > foo.bar = lambda: 1 > > > (Analogously, I would expect a definition like this: > > def baz[10](): return 1 > > to be equivalent to this: > > baz[10] = lambda: 1 ) > > > So, if, inside a class definition, I were to see this: > > def self.method(): return 1 > > Well, I'd understand that is was a method assigment, of course, but it > would conflict with what I would expect the natural meaning of > something like def a.b() would be. The above statement is not > equivalent to: > > self.method = lambda: 1 > > but I think that's what it ought to be, in general.
Similarly, to those coming from Ruby or those operating under the frequent misunderstanding that the `def`s are happening in the context of a class object (which in reality has yet to be created), `self` in this context might be misconstrued as the class object and thus `def self.foo` might be misunderstood (through the intuitive equivalence you mention) as a defining a classmethod rather than an instance method. I also strongly echo the TOOWTDI arguments against adding this duplicative syntax. It's a minor gain but costs much more than it's worth for violating The Zen. Cheers, Chris -- Follow the path of the Iguana... http://rebertia.com > > > > Carl Banks > > > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
