Climb - Property-based dispatch in functional languages

Transcript

1. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Property Based Dispatch in Functional
   Languages
   Christopher Chedeau
   LRDE
   Laboratoire de Recherche et D´
   eveloppement d’EPITA
   January 18, 2012
   http://lrde.epita.fr/
   1 / 19 Christopher Chedeau
   

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2. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Introduction
   Olena Properties
   Lisp Implementation
   Other Languages
   Conclusion
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3. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Olena Properties
   Type Name Values
   image dimension any, one d, two d, three d
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4. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Shift Algorithm
   definition
   any unique multiple varying
   Specialization (1)
   Specialization (2)
   size
   any fixed
   Specialization (1)
   Specialization (2)
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5. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   C++ Implementation
   shift(Window& win, mln dpsite(W)& dp) {
   // Dispatch on definition property
   shift (mln trait window definition(W)(), exact(win), dp);
   }
   shift (trait::window::definition::unique,
   W& win, mln dpsite(W)& dp) {
   /* Specialized implementation (1) */
   }
   shift (trait::window::definition::multiple,
   W& win, mln dpsite(W)& dp) {
   /* Specialized implementation (2) */
   }
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6. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Shift Algorithm
   definition
   any unique multiple varying
   Specialization (1) Ö Ö Ö
   Specialization (2) Ö Ö Ö
   size
   any fixed
   Specialization (1) Ö
   Specialization (2)
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7. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   C++ Implementation
   shift(Window& win, mln dpsite(W)& dp) {
   mlc is not(mln trait window definition(W),
   trait::window::definition::any)::check();
   mlc is not(mln trait window definition(W),
   trait::window::definition::varying)::check();
   shift (mln trait window definition(W)(), exact(win), dp);
   }
   shift (trait::window::definition::unique,
   W& win, mln dpsite(W)& dp) {
   mlc is(mln trait window size(W),
   trait::window::size::fixed)::check();
   }
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8. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Lisp Implementation
   (defmethod shift (
   (win window)
   (dp dpsite))
   ; Specialization (1)
   )
   (defmethod shift (
   (win window)
   (dp dpsite))
   ; Specialization (2)
   )
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9. Property Based Dispatch
   in Functional Languages
   Introduction
   Olena Properties
   Lisp
   Implementation
   Other Languages
   Conclusion
   Lisp Implementation
   (defalgo shift (
   (win
   :properties (
   :definition :unique
   :size :fixed)
   window)
   (dp dpsite))
   ; Specialization (1)
   )
   (defalgo shift (
   (win
   :properties (
   :definition :multiple)
   window)
   (dp dpsite))
   ; Specialization (2)
   )
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10. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Implementation Overview
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
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11. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Fibonacci
    (defalgo fibo ((n
    (lambda (n) (< n 2))))
    n)
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12. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Fibonacci
    (defalgo fibo ((n
    (lambda (n) (< n 2))))
    n)
    (defun <2 (n) (< n 2))
    (defalgo fibo ((n #’<2))
    n)
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13. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Fibonacci
    (defalgo fibo ((n
    (lambda (n) (< n 2))))
    n)
    (defun <2 (n) (< n 2))
    (defalgo fibo ((n #’<2))
    n)
    (defun is (a)
    (lambda (b)
    (eq a b)))
    (defalgo fibo ((n (is 0)))
    0)
    (defalgo fibo ((n (is 1)))
    1)
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14. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Fibonacci
    (defalgo fibo ((n
    (lambda (n) (< n 2))))
    n)
    (defun <2 (n) (< n 2))
    (defalgo fibo ((n #’<2))
    n)
    (defun is (a)
    (lambda (b)
    (eq a b)))
    (defalgo fibo ((n (is 0)))
    0)
    (defalgo fibo ((n (is 1)))
    1)
    (defalgo fibo (n)
    (+ (fibo (− n 2)) (fibo (− n 1))))
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15. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Javascript Full Dispatch
    fibo = FullDispatch()
    fibo.add [(n) −> n < 2],
    (n) −> n
    fibo.add [null],
    (n) −> fibo(n − 1) + fibo(n − 2)
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16. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Python Decorators
    @dispatch(inside(0, 1))
    def fibo(n):
    return n
    @dispatch(int)
    def fibo(n):
    return fibo(n − 1) + fibo(n − 2)
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17. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Haskell Pattern Matching
    fibo 0 = 0
    fibo 1 = 1
    fibo n = fibo (n − 1) + fibo (n − 2)
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18. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    MOP
    (defmethod fibo (n)
    (+ (fibo (− n 1)) (fibo (− n 2))))
    (defmethod fibo ((n (eql 1)))
    n)
    (defmethod fibo ((n (eql 0)))
    n)
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19. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Filtered Dispatch
    (defun state (n)
    (if (< n 2)
    ’terminal
    ’general))
    (defmethod fibo :filter :state ((n (eql ’terminal)))
    n)
    (defmethod factorial :filter :state ((n (eql ’general)))
    (+ (fibo (− n 1)) (fibo (− n 2))))
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20. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Multimethod.js
    fibo = multimethod()
    .dispatch((n) −> if n < 2
    ’terminal’
    else
    ’general’)
    .when(’terminal’,
    (n) −> n)
    .when(’general’,
    (n) −> fibo(n − 1) + fibo(n − 2))
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21. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Conclusion
    Conclusion
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22. Property Based Dispatch
    in Functional Languages
    Introduction
    Olena Properties
    Lisp
    Implementation
    Other Languages
    Conclusion
    Questions ?
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