The map a program over AndroidApp receives: the base set plus the process
continuation's reference. The reference's identifier is never (it is
closed over the base set when the layer is built), so it adds no requirement
to a program and is not part of AndroidRuntimeServices; it is picked so the
app layer's own screen actions can run it. The process reference
(CurrentAppProcess) is picked the same way: the transport reads it in every
request a program sends, so a checkpoint error names this process.
The map a program over
AndroidAppreceives: the base set plus the process continuation's reference. The reference's identifier isnever(it is closed over the base set when the layer is built), so it adds no requirement to a program and is not part ofAndroidRuntimeServices; it is picked so the app layer's own screen actions can run it. The process reference (CurrentAppProcess) is picked the same way: the transport reads it in every request a program sends, so a checkpoint error names this process.