Decorators implementation

[vitja]

Now decorators are implemented like this:

def foo():
   pass

foo = decorator(foo)

• first declare function in current scope
• then decorate it

This is not a big issue now, but when we will support function reassignment take a look at this example:

class Foo(object):
    _x = 0
    @property
    def x(self):
        return self._x
    @x.setter
    def x(self, value):
        self._x = value

# this code will be transformed into this

class Foo(object):
    _x = 0

    def x(self):
        return self._x
    x = property(x)

    def x(self, value):
        self._x = value
    x = x.setter(x)
    # this will raise AttributeError exception
    # as second x() doesn't have setter attribute

[vitja]

Testcase for issue

[scoder]

Fixed here:

 https://github.com/cython/cython/commit/37d6fac05af9250c214f25aaf2a11a5ab6326052

 https://github.com/cython/cython/commit/00c78163376bc057fbda14f4c642b40ab9d124f2

[scoder]

Reverted - currently breaks Sage:

 https://sage.math.washington.edu:8091/hudson/job/sage-build/453/console

[scoder]

Original fix reapplied here:

 https://github.com/cython/cython/commit/b309d5dd71be1e73ffaf27ecbb17d7ccdb1bc6e6

Sage problem is fixed here:

 https://github.com/cython/cython/commit/4c4c8674007b8c3ebd67392fd2847c6779ede793