46 lines
1.9 KiB
Markdown
46 lines
1.9 KiB
Markdown
### A thin layer
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Here we have a placeholder for things i am currently developing.
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Basically Parfait is the smallest amount of code needed to make a ruby-like OO system work.
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A work in progress that started from here : http://salama.github.io/2014/06/10/more-clarity.html went on here
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http://salama.github.io/2014/07/05/layers-vs-passes.html
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And i finally came to the conclusion that Parfait is the ruby runtime. Aha
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Run - time
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not compile - time
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always mixing those up: As such it is not loaded at compile time.
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A step back: the code (program) we compile runs at run - time.
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And so does parfait. So all we have to do is compile it with the program.
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And thus parfait can be used at run-time.
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It's too simple: just slips off the mind like a fish into water.
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#### Example: Message send
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I felt a little stupid that it took me so long to notice that sending a message is very closely relateed to the
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existing ruby method Object.send
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Off course object.send takes symbol and the arguments and has the receiver, so all the elements of our Messaage are there.
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And the process that Object.send needs to do is exactly that: send that message, ie find the correct method according to
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the old walk up the inheritance tree rules and dispatch it.
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And as all this happens at runtime, "all" we have to do is code this logic. And since it is at runtime, we can do it in ruby
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(as i said, this get's compiled and run, just like the program).
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But what about the infinite loop problem:
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There was a little step left out: Off course the method gets compiled at compile-time and so we don't just blindly dispatch:
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we catch the simple cases that we know about: layout, type instance variables and compile time known functions. Part of
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those are some that we just don't allow to be overridden.
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Also what in ruby is object.send is Message.send in salama, as it is the message we are sending and which defines all the
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data we need (not the object). The object receives, it does not send.
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