manpagez: man pages & more
man object(n)
Home | html | info | man
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  invocation  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 evalu-
              ation.

       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 sup-
              plied  to  the method are given as arg arguments.  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 names-
              pace 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 pro-
              cedures  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)

tcl 8.6.0 - Generated Sun Jan 13 13:21:42 CST 2013
© manpagez.com 2000-2024
Individual documents may contain additional copyright information.