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copied!<p>Read your proposal, have the following comments:</p> <ol> <li><p>There's actually no keyword to declare and define an actual state machine! Do you assume a single global state machine (and thus a single global state)? How does that relate to <code>__active__</code> ?</p></li> <li><p>The closest comparable construct in C++ is actually the enum. Why not extend it?</p></li> <li><p>There seems to be some connection between defined events and states, but I fail to see how it's implemented. </p></li> <li><p>Why are threads and timers needed at all? Some use cases of state machines may benefit from them, but a good proposal should keep these seperate. Most importantly this should allow the use of standard C++0x threads.</p></li> </ol> <p>Personally, I would extend the enum syntax:</p> <pre><code>enum Foo { red, blue, green; /* Standard C++ so far - defines states. State list ends with a ; not a , */ Foo() { *this = red; } // Reuse ctor syntax, instead of __initial__ ~Foo() { } // reuse dtor syntax, instead of __onexit__ void Bar() {/**/} // Defines an event, no return value. Doesn't need keyword __event__ }; </code></pre> <p>It follows naturally that you can now declare your events in a header, and define them in a .cpp file. I don't even need to suggest the syntax here, any C++ programmer can guess that at this point. Add a bit of inheritance syntax for combined states:</p> <pre><code>enum DrawingObject : public Shape, public Color { /** } // allows (red && circle) </code></pre> <p>and you're pretty much at the point where your proposal is, without any new keywords, all by reusing an already familiar syntax.</p>

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