Project

General

Profile

History

IDS declaration

The ids declaration declares a private, internal data structure.

The internal data structure stores global data shared by the services. Access to this structure is controlled by Genom, that takes care of the proper synchronization between concurrent access.

An IDS definition is similar to a struct definition, and follows this syntax:

(18) ids ::=

ids-name "{" member-list "}" ";"
(19) ids-name ::=

"ids"
(95) member-list ::=

{ member ";" } member ";"
(96) member ::=

( type-spec
| member "," ) declarator

The major difference with a regular struct is that an ids declaration can be reopened. Thus, several ids statements can be used to define an internal structure by independent chunks. This is useful for instance in case of included files.

Example

This would define the ids for the component foo, using two separate declarations:

component foo {
  ids {
    long state;
  };

  ids {
    double position;
    double velocity;
  };
};