Rubinius - Tales from the trenches @ Baruco 2012

Transcript

1. Rubinius
   Tales from the trenches
   

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2. Dirkjan Bussink
   @dbussink
   

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4. Huh?
   

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5. Class.stub!(:new).and_return(MyClass)
   

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6. Beyond
   imagination
   

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9. Liskov
   Substitution
   Principle
   

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10. class SomeList < Array
    def push(value)
    value = Proxy.new(value)
    if value.is_a?(String)
    ...
    end
    end
    alias_method :<<, :push
    end
    Unmarshal
    uses
    Array#<<
    

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11. StackError
    

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13. class PropertySet < Array
    alias_method :superclass_slice, :[]=
    private :superclass_slice
    def []=(name, property)
    self << property
    end
    def <<(property)
    found = named?(property.name)
    add_property(property)
    if found
    superclass_slice(index(property), property)
    else
    super
    end
    end
    end
    WUT?
    Ugh
    Oh, let’s change
    the meaning!
    

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14. class PropertySet
    def []=(name, property)
    add_property(property)
    end
    def <<(property)
    add_property(property)
    end
    def add_property(property)
    clear_cache
    @order << property unless @order.include?(@property)
    @properties[property.name] = property
    end
    end
    

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15. IDIOT
    

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16. GCC...
    

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17. vm/builtin/regexp.cpp:312: warning:
    control may reach end of non-void
    function
    

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19. GCC is fucking stupid.
    Avoid inane gcc type punning warning
    Work around GCC's broken strict aliasing checks.
    gcc 4.2.1 on freebsd 9 wants a newline at the end
    Make the gcc gods happy
    Make the stupid compiler gods happy
    Appease GCC 4.3
    

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20. Ruby is weird
    

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21. class MyClass
    def to_ary
    puts "we're here"
    [1]
    end
    end
    def my_method arg
    yield arg
    end
    my_method(MyClass.new) do |*arg|
    p arg
    end
    we're here
    [#]
    we're here
    [1]
    we're here
    [[1]]
    [#]
    A
    B
    C
    D
    Call to_ary and ignore
    

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22. can't define singleton method "method" for Float
    obj = 2.0
    def obj.method
    puts "method on float instance"
    end
    obj.method
    No singleton methods
    on Numeric
    

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23. class Numeric
    def singleton_method_added(name)
    end
    end
    obj = 2.0
    def obj.method
    puts "method on float instance"
    end
    obj.method
    method on float instance
    Singleton method
    on a Numeric!
    

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24. 3
    4
    5
    6
    Becomes true on first
    condition, false on second
    10.times do |i|
    if (i == 3) .. (i == 6)
    puts i
    end
    end
    

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25. Ruby’s C-API
    

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26. There is no C-API
    just internals of MRI that people use
    

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27. VALUE
    rb_data_object_alloc(VALUE klass, void *datap,
    RUBY_DATA_FUNC dmark, RUBY_DATA_FUNC dfree)
    {
    NEWOBJ(data, struct RData);
    if (klass) Check_Type(klass, T_CLASS);
    OBJSETUP(data, klass, T_DATA);
    data->data = datap;
    data->dfree = dfree;
    data->dmark = dmark;
    return (VALUE)data;
    }
    MRI internals
    

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28. NotImplementedError: method `class' called on terminated object (0xXXXXXXXX)
    Inspect object created with
    rb_data_object_alloc
    

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30. GC can
    be hard
    

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31. C Stack
    Object*
    Object*
    Heap 1
    Object
    Object
    Heap 2
    Object
    Object
    GC moves objects
    

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33. Old
    Young
    String Array
    Object
    String
    String Hash
    

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35. Concurrency
    is tricky
    

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36. Out of order
    execution
    

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37. a = 0
    b = 0
    c = 0
    d = 0
    Core 1 Core 2
    a = 1 c = 1
    b = 2 d = 2
    Statements can be executed
    in different order
    

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38. addr = Address.new
    addr.street = "Somestreet"
    addr.number = 1
    shared_addr = addr
    shared_addr => nil
    shared_addr => #
    shared_addr => #
    shared_addr => #
    shared_addr => #
    shared_addr = addr executed
    before other assignments
    

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39. addr = Address.new
    addr.street = "Somestreet"
    addr.number = 1
    Rubinius.memory_barrier
    shared_addr = addr
    

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40. Try your code
    We secretly love weird stuff
    

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