An EVE object offers a set of basic functions that can be invoked uniformly across all classes of EVE objects. Table 8.1 gives a summary of their names together with short explanations.
Table 8.1:
Summary of basic EVE functionality.
For the sake of conciseness, operations that are
equivalent for both controls and responses are not listed
separately.
Figure 8.5:
Three examples of the command Define-Control for defining
control variables.
alpha is declared as a control variable.
beta's value is derived from a LISP
expression using alpha. The internal
attribute marks the beta to be inaccessible to the client side.
gamma's value is converted to a string on the server side,
but not on the client side.
The define-control and define-response methods of an EVE object usually are invoked only once to establish a link with the server-side module. In general, a single control variable can have any number of connections to the server side. This mechanism is particularly useful when encapsulating process flows to map a single control variable to all appearances of a certain class of process or simulation parameter.