Joel Yliluoma wrote:

> Python:
> 
>   value = (lambda(x): 3*x+5)(42)
> 
> Lua:
> 
>   value = (function(x) return 3*x+5 end)(42)
> 
> Ruby (1):
> 
>   def test
>     yield 42
>   end
>   value = test { |x| 3*x+5 }
> 
> Ruby (2):
> 
>   value = lambda { |x| 3*x+5 } .call(42)
> 
> C++0x:
>   
>   int main()
>   {
>     int value = <>(int x) (3*x+5) (42);
>   }
> 
> i386 assembly (ok, this is cheating):
>   mov eax, 42
>   call over
>   lea eax, [eax*2+eax+5]
>   ret
> over:
>   pop eax
>   call eax
>   mov [value], eax

Haskell [is that cheating??]

   value = (\x -> 3*x + 5) 42

Lambda calculus:

   \i ->
   (\n -> \m -> \f -> \x -> n f (m f x))
   (
     (\n -> \m -> \f -> \x -> n (m f) x)
     (\f -> \x -> f (f (f x)))
     i
   )
   (\f -> \x -> f (f (f (f (f x)))))

[I can't be bothered to write "42" in the lambda calculus. Suffice it to 
say it contains 42 copies of the letter "f".]

-- 
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*

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