fun/mutrec.bruijn

# some example usage of the variadic fixed point combinator

:import std/List .
:import std/Logic .
:import std/Number .

# generates odd? and even? function as list
odd-even? y* (even? : {}odd?)
	even? [[[=?0 true (1 --0)]]]
	odd? [[[=?0 false (2 --0)]]]

:test (^odd-even? (+5)) (false)
:test (_odd-even? (+5)) (true)

# calculates n % 3
mod3 ^(y* (a : (b : {}c)))
	a [[[[=?0 (+0) (2 --0)]]]]
	b [[[[=?0 (+1) (1 --0)]]]]
	c [[[[=?0 (+2) (3 --0)]]]]

:test ((mod3 (+0)) =? (+0)) (true)
:test ((mod3 (+1)) =? (+1)) (true)
:test ((mod3 (+2)) =? (+2)) (true)
:test ((mod3 (+3)) =? (+0)) (true)
:test ((mod3 (+4)) =? (+1)) (true)
:test ((mod3 (+5)) =? (+2)) (true)
:test ((mod3 (+6)) =? (+0)) (true)
:test ((mod3 (+7)) =? (+1)) (true)
:test ((mod3 (+8)) =? (+2)) (true)
:test ((mod3 (+9)) =? (+0)) (true)

main [[0]]