copy(n) TclOO Commands copy(n) ______________________________________________________________________________
NAME
oo::copy - create copies of objects and classes
SYNOPSIS
package require TclOO
oo::copy sourceObject ?targetObject? ?targetNamespace?
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DESCRIPTION
The oo::copy command creates a copy of an object or class. It takes the
name of the object or class to be copied, sourceObject, and optionally
the name of the object or class to create, targetObject, which will be
resolved relative to the current namespace if not an absolute qualified
name and targetNamespace which is the name of the namespace that will |
hold the internal state of the object (my command, etc.); it must not |
refer to an existing namespace. If either targetObject or targetNames- |
pace is omitted or is given as the empty string, a new name is chosen. |
Names, unless specified, are chosen with the same algorithm used by the |
new method of oo::class. The copied object will be of the same class
as the source object, and will have all its per-object methods copied.
If it is a class, it will also have all the class methods in the class
copied, but it will not have any of its instances copied.
After the targetObject has been created and all definitions of its con- |
figuration (e.g., methods, filters, mixins) copied, the <cloned> method |
of targetObject will be invoked, to allow for customization of the cre- |
ated object such as installing related variable traces. The only argu- |
ment given will be sourceObject. The default implementation of this |
method (in oo::object) just copies the procedures and variables in the |
namespace of sourceObject to the namespace of targetObject. If this |
method call does not return a result that is successful (i.e., an error |
or other kind of exception) then the targetObject will be deleted and |
an error returned.
The result of the oo::copy command will be the fully-qualified name of
the new object or class.
EXAMPLES
This example creates an object, copies it, modifies the source object,
and then demonstrates that the copied object is indeed a copy.
oo::object create src
oo::objdefine src method msg {} {puts foo}
oo::copy src dst
oo::objdefine src method msg {} {puts bar}
src msg -> prints "bar"
dst msg -> prints "foo"
SEE ALSO
oo_class(n), oo_define(n), oo_object(n)
KEYWORDS
clone, copy, duplication, object
TclOO 0.1 copy(n)
tcl 8.6.7 - Generated Thu Aug 10 13:48:21 CDT 2017