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The Art of the Metaobject Protocol does not seem to go into any detail about senders sending blobs of data to receivers. What do you think it shows, exactly? Th

by 9rx 2y ago

The Art of the Metaobject Protocol does not seem to go into any detail about senders sending blobs of data to receivers. What do you think it shows, exactly? That you don't need to send blobs of data? That should be obvious by the fact that you can count the number of languages that support that concept on one hand, but does not remove that message passing when employed is necessarily dependent on runtime.

pjmlp 2y ago
It shows that message passing and types get along just fine.
- 9rx 2y ago
  It is not like they are sworn enemies, but as messages can originate from outside the program, they cannot be typed statically. It is impossible to know what types will appear before runtime. For messages that originate from within the same codebase, you can, perhaps, start to layer static typing on top, but it can only be a partial solution as it remains that messages can come from other sources.
  - pjmlp 2y ago
    Then we are talking about distributed computing, and nothing will help you understand that glob of undefined bytes. This has nothing to do with OOP.
    - 9rx 2y ago
      > Then we are talking about distributed computing You must have a funny definition of distributed computing, then. OO never really caught on, probably because accepting "globs of undefined bytes" is kind of sucky, but we see some examples in the wild. Interface Builder is probably the best example of where we really leaned into OO, orienting a program's UI objects from externally defined messages. I'm not sure what building user interfaces has to do with distributed computing, but... I guess?
      - pjmlp 2y ago
        "Messages that originate outside of the program" is distributed computing, regardless of it is on the same computing node, or across the network. Multiple processes are involved, giving meaning to a byte stream. I am quite sure Interface Builder has enough Objective-C type definitions, as does Portable Distributed Objects. Additionally, those mapping definitions on the UI are nothing else than a type system powering the whole experience.
        9rx 2y ago
        > Multiple processes are involved, giving meaning to a byte stream. Maybe in the case of Erlang, but that's a fairly unique case. Smalltalk[1], and by extension Objective-C, do not pass messages across processes. Languages don't normally concern themselves with that kind of thing at all. You can build distributed computing on top of languages (pretty much any language), but that's not a trait of the language and way beyond the topic at hand. [1] Which is what matters most as OO was literally defined by the design of Smalltalk.
        igouy 2y ago
        1987 "The design and implementation of distributed Smalltalk" https://dl.acm.org/doi/10.1145/38765.38836 https://dl.acm.org/doi/10.1145/38765.38836 https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/html/faqs/lang/oop/faq-doc-3.html https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/html/... > do not pass messages across processes Except "The Smalltalk-80 system provides support for multiple independent processes with three classes named Process, ProcessorScheduler, and Semaphore. A Process represents a sequence of actions that can be carried out independently of the actions represented by other Processes." "Ch. 15 Multiple Independent Processes" 1983 "Smalltalk-80 The Language and its Implementation" https://rmod-files.lille.inria.fr/FreeBooks/BlueBook/Bluebook.pdf https://rmod-files.lille.inria.fr/FreeBooks/BlueBook/Blueboo...

by 9rx 2y ago

pjmlp 2y ago

It shows that message passing and types get along just fine.

9rx 2y ago
It is not like they are sworn enemies, but as messages can originate from outside the program, they cannot be typed statically. It is impossible to know what types will appear before runtime. For messages that originate from within the same codebase, you can, perhaps, start to layer static typing on top, but it can only be a partial solution as it remains that messages can come from other sources.
- pjmlp 2y ago
  Then we are talking about distributed computing, and nothing will help you understand that glob of undefined bytes. This has nothing to do with OOP.
  - 9rx 2y ago
    > Then we are talking about distributed computing You must have a funny definition of distributed computing, then. OO never really caught on, probably because accepting "globs of undefined bytes" is kind of sucky, but we see some examples in the wild. Interface Builder is probably the best example of where we really leaned into OO, orienting a program's UI objects from externally defined messages. I'm not sure what building user interfaces has to do with distributed computing, but... I guess?
    - pjmlp 2y ago
      "Messages that originate outside of the program" is distributed computing, regardless of it is on the same computing node, or across the network. Multiple processes are involved, giving meaning to a byte stream. I am quite sure Interface Builder has enough Objective-C type definitions, as does Portable Distributed Objects. Additionally, those mapping definitions on the UI are nothing else than a type system powering the whole experience.
      - 9rx 2y ago
        > Multiple processes are involved, giving meaning to a byte stream. Maybe in the case of Erlang, but that's a fairly unique case. Smalltalk[1], and by extension Objective-C, do not pass messages across processes. Languages don't normally concern themselves with that kind of thing at all. You can build distributed computing on top of languages (pretty much any language), but that's not a trait of the language and way beyond the topic at hand. [1] Which is what matters most as OO was literally defined by the design of Smalltalk.
        igouy 2y ago
        1987 "The design and implementation of distributed Smalltalk" https://dl.acm.org/doi/10.1145/38765.38836 https://dl.acm.org/doi/10.1145/38765.38836 https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/html/faqs/lang/oop/faq-doc-3.html https://www.cs.cmu.edu/afs/cs/project/ai-repository/ai/html/... > do not pass messages across processes Except "The Smalltalk-80 system provides support for multiple independent processes with three classes named Process, ProcessorScheduler, and Semaphore. A Process represents a sequence of actions that can be carried out independently of the actions represented by other Processes." "Ch. 15 Multiple Independent Processes" 1983 "Smalltalk-80 The Language and its Implementation" https://rmod-files.lille.inria.fr/FreeBooks/BlueBook/Bluebook.pdf https://rmod-files.lille.inria.fr/FreeBooks/BlueBook/Blueboo...