DISPLAY [-tree] [-x] [-c class-name[:>method-name]] variable-name
display a variable [-tree: display as a tree] [-x: display as hexadecimal string]

DISPLAY [-x] [-c class-name[:>method-name]] {control-name}   {PROP}     property-name
        {control-handle} {PROPERTY}
        {window-handle}
display a property of a screen control or window

DISPLAY [-x] -env env-name
display an environment variable

DISPLAY -classinfo
display the class information of the current program