Decorating instance methods

[Alexander Draeger]

Hello everybody,

I'm very interesting in using the decorator concept, but I can't
convert it in useful things. I have read many about decorators and
have seen a lot of examples, but I search a possibility, to decorate
methods of classes with reference to the instances. For example:

I have a class A:

class A(object):
def __init__(self, name):
self.name=name

@logging
def hello(self, name):
print 'Hello World.'


Entering a method. [Ernie]
Hello World.
Entering a method. [Bert]
Hello World.


How should I implement the function logging, when I want to use the
variable self.name for the logging message?





Alex

 

[Diez B. Roggisch]

Hello everybody,

I'm very interesting in using the decorator concept, but I can't
convert it in useful things. I have read many about decorators and
have seen a lot of examples, but I search a possibility, to decorate
methods of classes with reference to the instances. For example:

I have a class A:

class A(object):
def __init__(self, name):
self.name=name

@logging
def hello(self, name):
print 'Hello World.'


Entering a method. [Ernie]
Hello World.
Entering a method. [Bert]
Hello World.


How should I implement the function logging, when I want to use the
variable self.name for the logging message?

def logging(m):
def _w(self, *args, **kwargs):
print "name:", self.name
returm m(self, *args, **kwargs)
return _w


Diez

 

[Duncan Booth]

Hello everybody,

I'm very interesting in using the decorator concept, but I can't
convert it in useful things. I have read many about decorators and
have seen a lot of examples, but I search a possibility, to decorate
methods of classes with reference to the instances. For example:

I have a class A:

class A(object):
def __init__(self, name):
self.name=name

@logging
def hello(self, name):
print 'Hello World.'


Entering a method. [Ernie]
Hello World.
Entering a method. [Bert]
Hello World.


How should I implement the function logging, when I want to use the
variable self.name for the logging message?

(Did you intend that other parameter to the hello method? If so you had
better pass it in when you call the method.)

Try this:
def deco(self, *args, **kw):
print "Entering a method [%s]" % self.name
return f(self, *args, **kw)
return deco
def __init__(self, name):
self.name=name

@logging
def hello(self, name):
print 'Hello World.'

Entering a method [Ernie]
Hello World.

 

[Cousin Stanley]

....
Try this:
....

Sesame __Street__ Version ....

'''
NewsGroup .... comp.lang.python
Subject ...... Decorating instance methods
Post_By ...... Alexander Draeger
Reply_By ..... Duncan Booth
Edit_By ...... Stanley C. Kitching
'''

def logging( f ) :

def deco( self , *args , **kw ) :

print " %s in da house !" % self.name
return f( self , *args , **kw )

return deco


class A( object ) :

def __init__( self , name ) :
self.name = name

@logging
def hello( self ) :
print ' Yo, %s .... \n' % self.name


def test_01() :

print

list_names = [ 'Bert' , 'Cookie Monster' ,
'Count Dracula' , 'Ernie' ]

list_objects = [ A( this_name ) for this_name in list_names ]

for this_object in list_objects :
this_object.hello()


if __name__ == '__main__' :

test_01()