is(n) [incr Tcl] is(n) ______________________________________________________________________________
NAME
is - test argument to see if it is a class or an object
SYNOPSIS
itcl::is option ?arg arg ...?
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DESCRIPTION
The is command is used to check if the argument given is a class or an
object; depending on the option given. If the argument if a class or
object, then 1 is returned. Otherwise, 0 is returned. The is command
also recognizes the commands wrapped in the itcl code command.
The option argument determines what action is carried out by the com-
mand. The legal options (which may be abbreviated) are:
is class command
Returns 1 if command is a class, and returns 0 otherwise.
The fully qualified name of the class needs to be given as the
command argument. So, if a class resides in a namespace, then
the namespace needs to be specified as well. So, if a class C
resides in a namespace N, then the command should be called
like:
is N::C
or
is ::N::C
is object ?-class className? command
Returns 1 if command is an object, and returns 0 otherwise.
If the optional "-class" parameter is specified, then the com-
mand will be checked within the context of the class given. Note
that className has to exist. If not, then an error will be
given. So, if className is uncertain to be a class, then the
programmer will need to check it's existance beforehand, or wrap
it in a catch statement.
So, if c is an object in the class C, in namespace N then these
are the possibilities (all return 1):
set obj [N::C c]
itcl::is object N::c
itcl::is object c
itcl::is object $obj
itcl::is object [itcl::code c]
KEYWORDS
class, object
itcl 3.3 is(n)
Mac OS X 10.8 - Generated Sat Sep 8 05:47:09 CDT 2012