nested function calls

[jonazza...@gmail.com]

Hi

How should we evaluate :

id x = x;
twice f x = f (f x) ;
main = twice id 6  ;

in good1.fun

as it requires another function?

[Aarne Ranta]

Hello,

Can you explain what you mean by "requires another function"? Everything that is needed is in the code.

The evaluation should go this way:

  main

  = twice id 6

  = (\f -> \x -> f (f x)) id 6

  = id (id 6)

  = (\x -> x) (id 6)

  = id 6

  = (\x -> x) 6

  = 6

Not necessarily in this order, but these are the main steps and the result.

Regards

  Aarne.