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Have a look at Objective-Smalltalk[1][2], with polymorphic identifiers[3] (all identifiers are URIs), storage combinators[4] (virtual filesystems on steroids),

Have a look at Objective-Smalltalk[1][2], with polymorphic identifiers[3] (all identifiers are URIs), storage combinators[4] (virtual filesystems on steroids), and polymorphic write streams[5] (streams everywhere). Objective-Smalltalk basically provides the sorts of things you write about locally at the language level. You could also move specific instances behind an operating system boundary. [1] https://objective.st https://objective.st [2] https://dl.acm.org/doi/10.1145/3689492.3690052 https://dl.acm.org/doi/10.1145/3689492.3690052 [3] https://dl.acm.org/doi/10.1145/2508168.2508169 https://dl.acm.org/doi/10.1145/2508168.2508169 [4] https://2019.splashcon.org/details/splash-2019-Onward-papers/7/Storage-Combinators https://2019.splashcon.org/details/splash-2019-Onward-papers... [5] https://dl.acm.org/doi/10.1145/3359619.3359748 https://dl.acm.org/doi/10.1145/3359619.3359748

black_knight 24d ago
Could you explain the connection you see a bit more? Part of the appeal of the Plan 9 approach was that you could use any program in your distributed environment, written in any language, because the abstraction layer was the file system – the lingua Franca of IO.
- mpweiher 23d ago
  Sure! To start: An operating system is a collection of things that don’t fit into a language. There shouldn’t be one. — Dan Ingalls, https://www.cs.virginia.edu/~evans/cs655/readings/smalltalk.html https://www.cs.virginia.edu/~evans/cs655/readings/smalltalk.... Let's start with an example, the Objective-Smalltalk equivalent of Python's simple web-server for a directory. Python: python3 -m http.server 8000 This serves the current directory on port 8000. The invocation for the Objective-Smalltalk script doing the equivalent job looks as follow: ./simplefileserver.st ./ 8000 Here is the Objective-Smalltalk 'simplefileserver.st' script: #!env st #-server: <ref>dir port: <int>port framework:ObjectiveHttpd load. dir asScheme waitOnPort: port. If you look carefully, you'll notice that this doesn't actually say anything about the filesystem. It just expects an argument 'dir' that is a 'ref' and then goes from there. Here are some other example of what a "ref" can be: ./simplefileserver.st https://objective.st 8000 ./simplefileserver.st sftp://otherhost.local 8000 ./simplefileserver.st env: 8000 ./simplefileserver.st defaults: 8000 ./simplefileserver.st class: 8000 ./simplefileserver.st scheme: 8000 The first will make this server act like an http proxy, the second will serve a remote directory, the third will serve our environment variables, the fourth will serve the contents of our process's defaults database (a macOS/iOS thing), the fifth our classes and the sixth the contents of the scheme registry where all the other schemes listed so far are registered. "Ref" is anything referencable by a polymorphic identifier, a slightly adapted version of a URI. And any ref can be turned into a store (aka "scheme-handler"). And a store can be literally anything that can store and retrieve data by key/index/name/path, from local variables via filesystems, databases all the way to the World Wide Web. So you can see that you can get the same location transparency that Plan 9 gives you without requiring operating system support. Which comes in handy when you can't switch to a new operating system. What's more, the support extends to a lot of things even Plan 9 probably wouldn't consider a filesystem (local variables?). Last not least, this does not require accessing everything via POSIX API and a byte-serialized representation. Definitely not "least"! You can access via a byte-serialized representation (as via the http server above) if you want, and you can even access via POSIX API (there is a generic fileserver that serves any of these stores / scheme handlers) if you really, really want. I am not at all sure why you would want that. And you can, of course, also access this via any language that can talk to C as the libraries that implement the functionality are written in portable Objective-C. Objective-Smalltalk just provides the proper linguistic support.

black_knight 24d ago

Could you explain the connection you see a bit more? Part of the appeal of the Plan 9 approach was that you could use any program in your distributed environment, written in any language, because the abstraction layer was the file system – the lingua Franca of IO.

mpweiher 23d ago
Sure! To start: An operating system is a collection of things that don’t fit into a language. There shouldn’t be one. — Dan Ingalls, https://www.cs.virginia.edu/~evans/cs655/readings/smalltalk.html https://www.cs.virginia.edu/~evans/cs655/readings/smalltalk.... Let's start with an example, the Objective-Smalltalk equivalent of Python's simple web-server for a directory. Python: python3 -m http.server 8000 This serves the current directory on port 8000. The invocation for the Objective-Smalltalk script doing the equivalent job looks as follow: ./simplefileserver.st ./ 8000 Here is the Objective-Smalltalk 'simplefileserver.st' script: #!env st #-server: <ref>dir port: <int>port framework:ObjectiveHttpd load. dir asScheme waitOnPort: port. If you look carefully, you'll notice that this doesn't actually say anything about the filesystem. It just expects an argument 'dir' that is a 'ref' and then goes from there. Here are some other example of what a "ref" can be: ./simplefileserver.st https://objective.st 8000 ./simplefileserver.st sftp://otherhost.local 8000 ./simplefileserver.st env: 8000 ./simplefileserver.st defaults: 8000 ./simplefileserver.st class: 8000 ./simplefileserver.st scheme: 8000 The first will make this server act like an http proxy, the second will serve a remote directory, the third will serve our environment variables, the fourth will serve the contents of our process's defaults database (a macOS/iOS thing), the fifth our classes and the sixth the contents of the scheme registry where all the other schemes listed so far are registered. "Ref" is anything referencable by a polymorphic identifier, a slightly adapted version of a URI. And any ref can be turned into a store (aka "scheme-handler"). And a store can be literally anything that can store and retrieve data by key/index/name/path, from local variables via filesystems, databases all the way to the World Wide Web. So you can see that you can get the same location transparency that Plan 9 gives you without requiring operating system support. Which comes in handy when you can't switch to a new operating system. What's more, the support extends to a lot of things even Plan 9 probably wouldn't consider a filesystem (local variables?). Last not least, this does not require accessing everything via POSIX API and a byte-serialized representation. Definitely not "least"! You can access via a byte-serialized representation (as via the http server above) if you want, and you can even access via POSIX API (there is a generic fileserver that serves any of these stores / scheme handlers) if you really, really want. I am not at all sure why you would want that. And you can, of course, also access this via any language that can talk to C as the libraries that implement the functionality are written in portable Objective-C. Objective-Smalltalk just provides the proper linguistic support.