52 lines
1 KiB
Lua
52 lines
1 KiB
Lua
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function churchZero()
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return function(x) return x end
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end
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function churchSucc(c)
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return function(f)
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return function(x)
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return f(c(f)(x))
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end
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end
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end
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function churchAdd(c, d)
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return function(f)
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return function(x)
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return c(f)(d(f)(x))
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end
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end
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end
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function churchMul(c, d)
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return function(f)
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return c(d(f))
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end
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end
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function churchExp(c, e)
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return e(c)
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end
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function numToChurch(n)
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local ret = churchZero
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for i = 1, n do
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ret = succ(ret)
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end
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return ret
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end
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function churchToNum(c)
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return c(function(x) return x + 1 end)(0)
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end
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three = churchSucc(churchSucc(churchSucc(churchZero)))
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four = churchSucc(churchSucc(churchSucc(churchSucc(churchZero))))
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print("'three'\t=", churchToNum(three))
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print("'four' \t=", churchToNum(four))
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print("'three' * 'four' =", churchToNum(churchMul(three, four)))
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print("'three' + 'four' =", churchToNum(churchAdd(three, four)))
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print("'three' ^ 'four' =", churchToNum(churchExp(three, four)))
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print("'four' ^ 'three' =", churchToNum(churchExp(four, three)))
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