# ----------------------------------------------------------------------------
# - EXP0805.als                                                              -
# - afnix example : chapter 8 : example 05                                   -
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# - copyright (c) 1999-2019 amaury darsch                                    -
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# combinator with factorial

# factorial - as a combinator
const c-fact (f) (gamma (n) (f) (if (== n 1) 1 (* n ((f f) (- n 1)))))

# the U combinator
const U (f) (f f)

# the generated factorial
const fact (U c-fact)

# let do the math
println "fact 5 = " (fact 5)
