declare In Out
A1=proc {$} X in {In get(X)} {Out set(X)} end
A2=proc {$} {W close} end
D=td(title:"Simple text I/O interface"
     lr(label(text:"Input:")
        text(handle:In  tdscrollbar:true glue:nswe)
        glue:nswe)
     lr(label(text:"Output:")
        text(handle:Out tdscrollbar:true glue:nswe)
        glue:nswe)
     lr(button(text:"Do It" action:A1 glue:nswe)
        button(text:"Quit"  action:A2 glue:nswe)
        glue:we))
W={QTk.build D}
{W show}