DragonFly On-Line Manual Pages

object(n)                       TclOO Commands                       object(n)

______________________________________________________________________________

NAME
       oo::object - root class of the class hierarchy

SYNOPSIS
       package require TclOO

       oo::object method ?arg ...?

CLASS HIERARCHY
       oo::object
______________________________________________________________________________

DESCRIPTION
       The oo::object class is the root class of the object hierarchy; every
       object is an instance of this class. Since classes are themselves
       objects, they are instances of this class too. Objects are always
       referred to by their name, and may be renamed while maintaining their
       identity.

       Instances of objects may be made with either the create or new methods
       of the oo::object object itself, or by invoking those methods on any of
       the subclass objects; see oo::class for more details. The configuration
       of individual objects (i.e., instance-specific methods, mixed-in
       classes, etc.) may be controlled with the oo::objdefine command.

       Each object has a unique namespace associated with it, the instance
       namespace.  This namespace holds all the instance variables of the
       object, and will be the current namespace whenever a method of the
       object is invoked (including a method of the class of the object). When
       the object is destroyed, its instance namespace is deleted. The
       instance namespace contains the object's my command, which may be used
       to invoke non-exported methods of the object or to create a reference
       to the object for the purpose of invokation which persists across
       renamings of the object.

   CONSTRUCTOR
       The oo::object class does not define an explicit constructor.

   DESTRUCTOR
       The oo::object class does not define an explicit destructor.

   EXPORTED METHODS
       The oo::object class supports the following exported methods:

       obj destroy
              This method destroys the object, obj, that it is invoked upon,
              invoking any destructors on the object's class in the process.
              It is equivalent to using rename to delete the object command.
              The result of this method is always the empty string.

   NON-EXPORTED METHODS
       The oo::object class supports the following non-exported methods:

       obj eval ?arg ...?
              This method concatenates the arguments, arg, as if with concat,
              and then evaluates the resulting script in the namespace that is
              uniquely associated with obj, returning the result of the
              evaluation.

       obj unknown ?methodName? ?arg ...?
              This method is called when an attempt to invoke the method
              methodName on object obj fails. The arguments that the user
              supplied to the method are given as arg argments.  If methodName |
              is absent, the object was invoked with no method name at all (or |
              any other arguments).  The default implementation (i.e., the one
              defined by the oo::object class) generates a suitable error,
              detailing what methods the object supports given whether the
              object was invoked by its public name or through the my command.

       obj variable ?varName ...?
              This method arranges for each variable called varName to be
              linked from the object obj's unique namespace into the caller's
              context. Thus, if it is invoked from inside a procedure then the
              namespace variable in the object is linked to the local variable
              in the procedure. Each varName argument must not have any
              namespace separators in it. The result is the empty string.

       obj varname varName
              This method returns the globally qualified name of the variable
              varName in the unique namespace for the object obj.

       obj <cloned> sourceObjectName
              This method is used by the oo::object command to copy the state
              of one object to another. It is responsible for copying the
              procedures and variables of the namespace of the source object
              (sourceObjectName) to the current object. It does not copy any
              other types of commands or any traces on the variables; that can
              be added if desired by overriding this method in a subclass.

EXAMPLES
       This example demonstrates basic use of an object.
              set obj [oo::object new]
              $obj foo             -> error "unknown method foo"
              oo::objdefine $obj method foo {} {
                  my variable count
                  puts "bar[incr count]"
              }
              $obj foo             -> prints "bar1"
              $obj foo             -> prints "bar2"
              $obj variable count  -> error "unknown method variable"
              $obj destroy
              $obj foo             -> error "unknown command obj"

SEE ALSO
       my(n), oo::class(n)

KEYWORDS
       base class, class, object, root class

TclOO                                 0.1                            object(n)