[Tutor] Know Thy Self

[Joseph J. Strout]

At 9:19 AM -0700 04/13/99, Arne Mueller wrote:

>As far as I know it's a referecne to the calling object.

No, it's a reference to the object by which a method was invoked.  Let's
make a simpler example:

class Spammer:

	def __init__(self):
		self.str = "spam "
		# note: don't use 'string' for a variable; it's a module!

	def spam(self,n):
		print self.str * n

foo = Spammer()		# create a Spammer object
foo.spam(5)		# tell it to spam


You see, when you say "foo.spam(5)", this is implicitly converted to:
	Spammer.spam(foo,5)

And so within that method, 'self' refers to 'foo'.  That's it.  That's all
that's going on.  Note that it does *not* refer to the calling object... in
the example above, there is NO calling object it might refer to!  If you
want to pass a reference to the calling object to another object's method,
you'll have to pass it in explicitly like any other parameter.

Cheers,
-- Joe
,------------------------------------------------------------------.
|    Joseph J. Strout           Biocomputing -- The Salk Institute |
|    joe@strout.net             http://www.strout.net              |
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