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Comment by solox3 | Hacker News Reader

I wonder how multiple inheritance is handled by this webdev holy grail. I know CoffeeScript had some issues handling its certain attributes* within its constructors, so it'll be interesting to see how pythonium does the same and beyond.

* forgot what

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    > I know CoffeeScript had some issues handling its certain attributes* 
    > within its constructors

Oh really? Do tell.

    class a
      constructor: ->
        # conventionally logs 3
        console.log @c

    class b extends a
      c = 3

    new b()  # logs undefined

Not quite. Key-value properties use the colon syntax. Regular assignment is for local variables. Your "c" is a local variable within the class body of "b", and should absolutely not be visible from the constructor of "a".

Here's the corrected version:

    class a
      constructor: ->
        console.log @c

    class b extends a
      c: 3

    new b()  # logs 3

Today the whole office learned. Thanks a bunch, Jeremy!

I hope your object model doesn't require understanding the MRO to trace the code, unless you're doing some serious library plumbing that I can't even really fathom using in front-end code right now. But I'm fairly certain you could mimic those semantics with wrappers around prototypal inheritance somehow.

It's not possible to use prototypal inheritance to mock even simple inheritance since “method = object.metod; method();” loose the reference to “this” as “object”, it's a gotcha in the lower level mode Veloce of Pythonium that I tried to explain in https://github.com/pythonium/pythonium/wiki/Pythonium-Veloce.... The MRO and thus multiple inhertiance is implemented in pythonium_create_class https://github.com/pythonium/pythonium/blob/master/pythonium...

Yeah, that's why I phrased it "wrappers around". Check out https://github.com/lukasolson/Backbone-Super for example, which wraps and replaces Backbone.extend.

I never mentionned super. Anyway, thanks for the link.

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