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44 lines
1019 B
Plaintext
44 lines
1019 B
Plaintext
1 Context
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This spec defines one function, Nock.
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2 Structures
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A noun is an atom or a cell. An atom is any unsigned integer.
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A cell is an ordered pair of any two nouns.
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3 Pseudocode
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Brackets enclose cells. [a b c] is [a [b c]].
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*a is Nock(a). Reductions match top-down.
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4 Reductions
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?[a b] => 0
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?a => 1
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^[a b] => ^[a b]
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^a => (a + 1)
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=[a a] => 0
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=[a b] => 1
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=a => =a
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/[1 a] => a
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/[2 a b] => a
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/[3 a b] => b
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/[(a + a) b] => /[2 /[a b]]
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/[(a + a + 1) b] => /[3 /[a b]]
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/a => /a
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*[a 0 b] => /[b a]
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*[a 1 b] => b
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*[a 2 b c d] => *[a 3 [0 1] 3 [1 c d] [1 0] 3 [1 2 3] [1 0] 5 5 b]
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*[a 3 b] => **[a b]
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*[a 4 b] => ?*[a b]
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*[a 5 b] => ^*[a b]
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*[a 6 b] => =*[a b]
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*[a [b c] d] => [*[a b c] *[a d]]
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*a => *a
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