1is(n)                             [incr Tcl]                             is(n)
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NAME

8       itcl::is - test argument to see if it is a class or an object
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SYNOPSIS

11       itcl::is option ?arg arg ...?
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DESCRIPTION

16       The  is command is used to check if the argument given is a class or an
17       object; depending on the option given. If the argument if  a  class  or
18       object,  then  1 is returned. Otherwise, 0 is returned.  The is command
19       also recognizes the commands wrapped in the itcl code command.
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21       The option argument determines what action is carried out by  the  com‐
22       mand.  The legal options (which may be abbreviated) are:
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24       is class command
25              Returns 1 if command is a class, and returns 0 otherwise.
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27              The  fully  qualified name of the class needs to be given as the
28              command argument. So, if a class resides in  a  namespace,  then
29              the  namespace  needs  to be specified as well. So, if a class C
30              resides in a namespace N, then  the  command  should  be  called
31              like:
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33                     is N::C
34                         or
35                     is ::N::C
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37       is object ?-class className? command
38              Returns 1 if command is an object, and returns 0 otherwise.
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40              If  the  optional "-class" parameter is specified, then the com‐
41              mand will be checked within the context of the class given. Note
42              that  className  has  to  exist.  If  not, then an error will be
43              given. So, if className is uncertain to be  a  class,  then  the
44              programmer will need to check it's existance beforehand, or wrap
45              it in a catch statement.
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47              So, if c is an object in the class C, in namespace N then  these
48              are the possibilities (all return 1):
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50                     set obj [N::C c]
51                     itcl::is object N::c
52                     itcl::is object c
53                     itcl::is object $obj
54                     itcl::is object [itcl::code c]
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KEYWORDS

57       class, object
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62itcl                                  3.3                                is(n)
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