package require Itcl
  itcl::class helloworld {
    public variable owner "No-one"
    method greet {} { puts "Hello World from $owner" }
  }
  itcl::class goodbyeworld {
    public variable owner "No-one"
    method greet {} { puts "Goodbye Cruel World from $owner" }
  }
  helloworld  h1
  goodbyeworld h2
  h1 configure -owner Me
  h2 configure -owner You
  h1 greet
  h2 greetThe following reports that both h1 and h2 are itcl objects.puts "Variable h1 [itcl::is object h1] h2 [itcl::is object h2]"This snippet reports that h1 is a helloworld, but h2 is not.
puts "Variable h1 [itcl::is object h1 -class helloworld] h2 [itcl::is object h2 -class helloworld]"
A similar method "isa" has been added which returns a logical:
- h1 isa helloworld
puts "Hey [h1 isa helloworld]"
- Hey 1
puts "Hey [h1 isa goodbyeworld]"
- Hey 0
puts "Hey [h1 isa sausage]"
- class "sausage" not found in context "::helloworld"
h1 info class
- ::helloworld

