[Python-Dev] A syntax for function attributes?

Pat Miller patmiller@llnl.gov
Thu, 31 Jul 2003 07:53:41 -0700

Michael wrote:
> I don't object to a syntax for function attributes... in fact, I've seen no
> specific proposal to object to. But I find your point above HIGHLY
> unconvincing:

I agree that

def sqr(x):
    return x*x
sqr.inline = true

is about the same length as

def sqr [inline=true](x):
    return x*x

But when this function is 60 lines long rather than 2 lines long, the
association is broken.  This is my major objection, not the number
of characters I write, but rather the number of lines I must scan.

People wouldn't be as likely to use doc strings if the syntax was:

def function(x):
     code code code
function.__doc__ = "this is my doc string"

> Notice that this is the approach that Guido used for classmethod and
> its ilk, and we're still working out what the right "special syntax"

I use the classmethod call because its the only (good) way to do
the task, but I have the same objection.  When I write

class Foo:
    def method(self, ...):

    method = classmethod(method)

Upon reading, I don't find out the "true meaning" of the method until I
happen upon the classmethod call.

Even in C++ with its bogus syntax, I can identify a class method at the
point of definition

class Foo {
    static void method(...);

so, it would be nice if there was a way to densely associate the
information at the point of function definition just as the doc
string is densely associated with the function definition.

class Foo:
    def method [classmethod=true](self, ...):
          "doc string"

    def get_x [property="x"](self):
         return self.__x

Patrick Miller | (925) 423-0309 | http://www.llnl.gov/CASC/people/pmiller

The more original a discovery, the more obvious it seems afterward.
  -- Arthur Koestler