Teachpacks for How to Design Programs

# Lkup GUI

### lkup-gui.ss

The teachpack `lkup-gui.ss` implements three functions:

- `control : -> symbol`
  to read out the name that a user typed into the query field
- `view : (union string symbol) -> true`
  to display its argument in the message panel
- `modelT = (button% event% -> true)`
  `connect : modelT -> true`
  to connect a controller with the Check button displays frame

  Example:

      (connect
       (lambda (e b)
         (view (control))))

  This example simply mirrors what the user types in to the message field.