A module in SAP Sybase Event Stream Processor offers reusability; it can be loaded and used multiple times in a single project or in many projects.
Modularity means organizing project elements into self-contained, reusable components called modules, which have well-defined inputs and outputs, and allow you to encapsulate data processing procedures that are commonly repeated.
Modules, along with other objects such as import files and the main project, have their own scope, which defines the visibility range of variables or definitions. Any variables, objects, or definitions declared in a scope are accessible within that scope only; they are inaccessible to the containing scope, called the parent scope, or to any other outer scope. The parent scope can be a module or the main project. For example, if module A loads module B and the main project loads module A, then module A's scope is the parent scope to module B. Module A's parent scope is the main project.
Modules have explicitly declared inputs and outputs. Inputs to the module are associated with streams or windows in the parent scope, and outputs of the module are exposed to the parent scope using identifiers. When a module is reused, any streams, variables, parameters, or other objects within the module replicate, so that each version of the module exists separately from the other versions.
You can load modules within other modules, so that module A can load module B, which can load module C, and so on. Module dependency loops, however, are invalid. For example, if module A loads module B, which loads A, the CCL compiler generates an error indicating a dependency loop between modules A and B.