announce kernel result

[plastikfan]

this will include adding any support code enale tests to be completed, eg registering the session so that it can be populated on the KernelResult.

[plastikfan]

approaches to consider:

• register the session with the navigator: before navigation starts, the session needs to be able to invoke something provided by the navigator (facilities). This could be an internal bus event: navigation.before and would allow other entities to provide data required for the result; ForResult. The problem with this approach is that the navigator has to know about external concerns; ie setting the session on the result.
• broadcast kernel result: this would be a bus event, whose data field would be the KernelResult. Entities interested in the KernelResult would register a handler for the KernelResult, so that they can set properties on the result. This frees the navigator from external concerns, it just broadcasts something and the other entites can do whatever they need to. This is the prefered approach as it maintains separation of concerns.

[plastikfan]

So broadcasting the result should be done by the base navigator/agent with a function called result. The problem we have here is that we only want the result to be announced once, which poses problems for Spawn, which produces many results for a single navigation. To get around this issue, the announce should be defined by the session. So we need to register the session with the navigator but for a different reason than was discussed in the previous post.

Spawn knows when the result really means a final result, so it needs to be able overriden the core navigator.