set form_def {
  GuidoForm form {
    -label "GuidoField Form"
    -default_buttons

    GuidoField number {
      -label "Enter a real number"
      -format double
      -width 10
      -low_bound 0
      -high_bound 100
      -null false
    }
  }
}
SclCreateGuidoForm form_handle $form_def {}
$form_handle SclRun {}

puts "The number is $number"
