Average rating:
set evalcmd [lcdui.command -label Evaluate -longlabel Evaluate]
set textbox [lcdui.textbox -text {[lcdui.alert -text "hi!"] setcurrent} \
-commandaction runCode]
$textbox setcurrent
$textbox addcommand $evalcmd
proc runCode {cmd txtbox} {
eval [$txtbox cget -text]
}