+/R
    +/R takes an entity
    specification, which is a cons pair with a relation in its CAR and an
    expression, evaluating to an object, in its CDR. For example:
    
    '(text : home obj)
    +/R is used in locked, read-only, GUI components. It does not
    modify the value in the object. However, that does not happen in '+Lock'ed
    components anyway. See also +E/R, +Lock.
+Radio
    
    '(<grid> 2
        "Radio A" (gui '(+Var +Radio) '*DemoRadio NIL "A")
        "Radio B" (gui '(+Radio)  -1 "B")
        "Radio C" (gui '(+Radio)  -2 "C") )
    +Radio components only makes sense as a group. The first argument to a +Radio component is either NIL or a field reference. If the first argument is NIL, the component in question will be the 'leader component' of a radio group. In the example above "Radio A" holds this position.
The following +Radio components in our example have a field reference as their first argument. This reference points back to the 'leader component' of the radio group. Our example uses a relative, numeric, offset to another field, but the symbolic name of a field can also be used.
The 'leader component' of a radio group takes care of holding the resulting value. As can be seen above, the first +Radio component uses a prefix class, +Var. This class is used to connect a variable to a gui component. Since this is the 'leader' of the radio group, its variable (*DemoRadio) will be populated with the value that results from selecting one of the radio buttons.
See also gui, +field and input fields.+RedoButton
    (repl Attr)
    +RgbPicker
   <input
   type="color"...> . See also +field.
+Rid
 
 "Some text" (gui (+Rid +TextField) 30)
 +Able expression, which may
 happen to disable it again. See also +Able.
(resetButton Lst)
    
    (resetButton '(nr nm pr sup query)) )
    (row D)
    
    (de row (D)
       (+ (: chart 1 ofs) (: chart 2) -1 (or D 0)) )