# ---------------------------------------------------------------------------
# - 0804.als                                                                -
# - afnix example : chapter 8 : example 04                                  -
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# - copyright (c) 1999-2007 amaury darsch                                   -
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# SKI combinators exampl, form transformation (+ x x)

# the S combinator
const S (f) (gamma (g) (f) (gamma (x) (f g) ((f x) (g x))))

# the K combinator
const K (x) (gamma (y) (x) (eval x))

# the I combinator
const I (x) (eval x)

# curried '+' operator
const c+ (x) (gamma (y) (x) (+ x y))

# testing the reduction (+ x x) => (S ((S (K +)) I)) I)
println "((+ x x) 512) = " (((S ((S (K c+)) I)) I) 512)