Exyz

Provides a Z-combinator (but no Y-combinator) macro and function to facilitate recursive anonymous functions.

What is a Z-combinator?

It's a strict fixed point combinator.

What's a strict fixed point combinator

It's a fixed point combinator for strict languages.

What's a fixed point combinator

It's a higher order function thats result, when used as input again, is the same.

What?

( ͡° ͜ʖ ͡° )

Usage

With the function:

iex(1)> factorial = Exyz.z_combinator fn(f) ->
...(1)>   fn
...(1)>     (1) -> 1
...(1)>     (n) -> n * f.(n - 1)
...(1)>   end
...(1)> end
iex(2)> factorial.(5) == 120
true

Or save two lines with the macro:

iex(1)> factorial = Exyz.z fn
...(1)>   (1) -> 1
...(1)>   (n) -> n * this.(n - 1)
...(1)> end
iex(2)> factorial.(5) == 120
true