> Your editor's inner state, for instance, is not visible to other applications, so you need to come up with your own whole programming scheme.
> Same with your window manager.
> You don't need to build your own programming language for Acme, because Acme's state is visible as a filesystem.
I don't see how it's good programming practice to expose your internal state to direct read/write access from other programs. It seems to violate basic encapsulation principles.
Your quotes are making me think of some really important takeaways from the Longhorn disaster with WinFS, detailed in a recent submission[1]:
> More profoundly, Bill’s vision of an ecosystem of applications that all store and share their data in this relational store is in direct conflict with how applications build their data models. While some desktop applications (and almost all internal IT-written ones) use relational stores for their internal data model, they do not want to expose those data models for unmonitored read and write by other applications. I detailed some of the fundamental reasons in the post referenced above, Leaky by Design.[2]
Solutions like this... "what if application state were like a relational data store, or hierarchical FS, that other programs can access", sounds great as a fun programming exercise, but it isn't often how people actually want to design applications.
By "inner state", the parent didn't mean literally the RAM or disk storage used internally by the application, just the logical state that belongs to it. A Plan 9 filesystem is just an interprocess communication API that happens to be structured in terms of virtual 'files' and file operations, kind of like what REST does with HTTP. The application handles all requests itself so it can always limit access or enforce invariants, which was absent in the Microsoft examples you linked.
> Same with your window manager.
> You don't need to build your own programming language for Acme, because Acme's state is visible as a filesystem.
I don't see how it's good programming practice to expose your internal state to direct read/write access from other programs. It seems to violate basic encapsulation principles.
Your quotes are making me think of some really important takeaways from the Longhorn disaster with WinFS, detailed in a recent submission[1]:
> More profoundly, Bill’s vision of an ecosystem of applications that all store and share their data in this relational store is in direct conflict with how applications build their data models. While some desktop applications (and almost all internal IT-written ones) use relational stores for their internal data model, they do not want to expose those data models for unmonitored read and write by other applications. I detailed some of the fundamental reasons in the post referenced above, Leaky by Design.[2]
Solutions like this... "what if application state were like a relational data store, or hierarchical FS, that other programs can access", sounds great as a fun programming exercise, but it isn't often how people actually want to design applications.
[1] https://hackernoon.com/what-really-happened-with-vista-4ca7f... [2] https://hackernoon.com/leaky-by-design-7b423142ece0