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(python2.1-tut.info)Class Definition Syntax

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Class Definition Syntax
-----------------------

The simplest form of class definition looks like this:

     class ClassName:
         <statement-1>
         .
         .
         .
         <statement-N>

Class definitions, like function definitions (`def' statements) must be
executed before they have any effect.  (You could conceivably place a
class definition in a branch of an `if' statement, or inside a
function.)

In practice, the statements inside a class definition will usually be
function definitions, but other statements are allowed, and sometimes
useful -- we'll come back to this later.  The function definitions
inside a class normally have a peculiar form of argument list, dictated
by the calling conventions for methods -- again, this is explained
later.

When a class definition is entered, a new namespace is created, and
used as the local scope -- thus, all assignments to local variables go
into this new namespace.  In particular, function definitions bind the
name of the new function here.

When a class definition is left normally (via the end), a _class
object_ is created.  This is basically a wrapper around the contents of
the namespace created by the class definition; we'll learn more about
class objects in the next section.  The original local scope (the one
in effect just before the class definitions was entered) is reinstated,
and the class object is bound here to the class name given in the class
definition header (`ClassName' in the example).