All action statements can be executed during runtime only, and must be contained within a response definition or action routine. In most action statements, you supply the name (identifier) of the object upon which the statement is to act. For example, the statement:

 

response to Reduce

    delete Triangle

 

deletes the definition of the object named Triangle and, in this case, all of Triangle's children. You can specify either a single object or a class of objects; if you specify a class, the statement acts on all objects in the class. (See Using Classes of Objects for details on how action statements affect classes of objects.)

 

In place of a name, you can specify a string variable, including any of the valid built-in functions, that is to be converted to a name. ESL performs this conversion according to the conversion rules presented in Type Conversions. For example, you can specify any of the following:

 

response to line from keyboard        # The typed lines are

    add to TextDisplay                # displayed in the

        insert input                        # region TextDisplay.

or:

response to DisabledKeyClass

    delete object                        # object is a built-in function.

or:

response to ...

    copy DisabledKey to DisabledKeyName

        append Counter to DisabledKeyName

                                    # DisabledKeyName is a string

        delete DisabledKey              # variable.