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71 lines
1.4 KiB
Plaintext
71 lines
1.4 KiB
Plaintext
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Author: Mencius Moldbug [moldbug@gmail.com]
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Date: 9/15/2008
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Version: 10K
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1. Introduction
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This file defines one function, "nock."
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nock is in the public domain.
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2. Data
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A "noun" is either an "atom" or a "cell." An "atom" is an unsigned
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integer of any size. A "cell" is an ordered pair of any two nouns,
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the "head" and "tail."
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3. Semantics
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nock maps one noun to another. It doesn't always terminate.
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4. Pseudocode
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nock is defined in a pattern-matching pseudocode, below.
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Brackets enclose cells. [a b c] is [a [b c]].
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5. Definition
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5.1 Transformations
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*[a [b c] d] => [*[a b c] *[a d]]
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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] => *[a]
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5.2 Operators
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5.2.1 Goto [*]
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*[a] -> nock[a]
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5.2.2 Deep [&]
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&[a b] -> 0
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&[a] -> 1
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5.2.4 Bump [^]
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^[a b] -> ^[a b]
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^[a] -> (a + 1)
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5.2.5 Like [=]
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=[a a] -> 0
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=[a b] -> 1
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=[a] -> =[a]
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5.2.6 Snip [/]
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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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