# helloWorld.tcl
 #!/bin/sh
 # the next line restarts using tclsh \
 exec tclsh "$0" "$@"

 # load the Gnocl package
 package require Gnocl

 # create a button, print 'Hello World' to console when clicked.
 set but1 [gnocl::button -text "Click Me!" -onClicked {puts "Hello World"}]

 # create a container to hold the widget, not necessary but we want to keep the button small
 set box [gnocl::box]

 # add the button to the container, using -fill {0 0} will restrict the size,
 # but allow its position to be adjusted when the window is resized
 $box add $but1 -fill {0 0} -expand 1

 # create the window, the parameters speak for themselves
 gnocl::window -title "helloWorld.tcl" -onDelete {exit} -child $box -widthRequest 200 -heightRequest 50

 # not necessary, but programmatically correct
 gnocl::mainLoop