22 lines
363 B
Factor
22 lines
363 B
Factor
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USE: stack
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USE: math
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USE: kernel
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USE: combinators
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USE: compiler
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USE: test
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! http://inferno.bell-labs.com/cm/cs/who/bwk/interps/pap.html
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: ack ( m n -- )
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over 0 = [
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nip succ
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] [
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dup 0 = [
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drop pred 1 ack
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] [
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dupd pred ack >r pred r> ack
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] ifte
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] ifte ; compiled
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[ 4093 ] [ 3 9 ack ] unit-test
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