Re: Proc#curry doesn't work on func which produces func

2008/3/2, ts <[e-mail]>:
>  How do you do this ?
>
> vgs% cat cur.rb
> class A
>   define_method(:a) do |x, y|
>      puts "a #{x} -- #{y}"
>   end
> end
>
> class B
>   def a(x)
>      puts "b #{x}"
>   end
> end
>
> a = :a.to_proc.curry
> b = a[A.new]
> c = b[12]
> c[12]
>
> b = a[B.new]
> b[12]
>
> vgs%
>
>
> vgs% ./ruby cur.rb
> a 12 -- 12
> b 12
> vgs%

Aha, I didn't know what Symbol#to_proc is.  It is indeed a
feature that :foo.to_proc.arity is -1.

Well, though it is slightly confusing to change the number
of arguments dynamically
  - depending on the first argument, and
  - only when the proc is made from Symbol#to_proc,
it may be also essential.  I wonder if I should change
Proc#curry.


By the way, I'm curious to know what purpose do people use
Proc#curry for.
I suggested it to define SKI combinator more simply, but I
don't feel so many people play with SKI combinator ;)

  s = proc {|f, g, x| f[x][g[x]] }.curry
  k = proc {|x, y| x }.curry

-- 
Yusuke ENDOH <[e-mail]>