Creating subclassess (newbie)

[Adam]

I have tried to send this to the tutor mailing list, but it
seems to be down at the moment.

I have a subclass I want to create- my intuition told me
that it would be done like this:

class MainClass:
class SubClass:
code...
subclassinstance = SubClass()
mainclassinstance = MainClass()

But it seems that this isn't going to work. I'm reading a
couple of Python books, but they don't seem to cover this
topic very well (I don't see any coding examples).

What is the best way of creating (coding) subclasses?
Alternatively, is there any good documentation on the web
for doing this?

Thanks in advance.

Adam

 

[Peter Hansen]

I have a subclass I want to create- my intuition told me
that it would be done like this:

class MainClass:
class SubClass:
code...
subclassinstance = SubClass()
mainclassinstance = MainClass()

Have you followed through the tutorial in the documentation?
The section on classes covers inheritance in a basic way.
See
http://www.python.org/doc/current/tut/node11.html#SECTION0011500000000000000000

-Peter

 

[Duncan Booth]

What is the best way of creating (coding) subclasses?
Alternatively, is there any good documentation on the web
for doing this?

Have you tried reading the Python tutorial? http://docs.python.org/tut if
you can't find it on your own machine. Try reading chapter 9: 'classes'
with special attention to 9.5 'inheritance'.

If you want coding examples you could look at Python's standard library.
There are plenty of examples of subclassing. For example, try CGIHTTPServer
and its associated documentation, htmllib or HTMLParser are other places
to look.

http://docs.python.org/lib/htmlparser-example.html shows an example of
subclassing the HTMLParser class to parse html.

 

[Lonnie Princehouse]

Typically, "subclass" refers to a derived class. It looks like you've
interpreted it in a different way, to mean a class that is a member of
another class? Interesting =)

subclass example-

class MainClass:
def foo(self):
return 'main_foo'
def bar(self):
return 'main_bar'

class SubClass(MainClass):
def foo(self):
return 'sub_foo'
main_bar

 

[Piet van Oostrum]

A> I have tried to send this to the tutor mailing list, but it
A> seems to be down at the moment.

A> I have a subclass I want to create- my intuition told me
A> that it would be done like this:

A> class MainClass:
A> class SubClass:
A> code...
A> subclassinstance = SubClass()
A> mainclassinstance = MainClass()

A> But it seems that this isn't going to work. I'm reading a
A> couple of Python books, but they don't seem to cover this
A> topic very well (I don't see any coding examples).

I can't imagine that the Python books don't tell this.

A> What is the best way of creating (coding) subclasses?
A> Alternatively, is there any good documentation on the web
A> for doing this?

I guess every Python introduction tells you:

class MainClass:
....

class SubClass(MainClass):
....

mainclassinstance = MainClass()
subclassinstance = SubClass()