You can tell ESL to perform the specified action statements when the user selects any object that is a member of the specified class by specifying the object built-in function. (This function is described in Using Response Inquiry Built-in Functions.)  For example, suppose you have defined a class named Keys:

 

class Keys is Key1 Key2 Key3 Key4

 

If the following response definition is specified:

 

response to Keys

    make Keys magenta

    make object white

 

then selecting any of the selectable keys in the class - Key1, Key2, Key3, or Key4 - results in all the keys selected turning magenta, then the one selected turning white.