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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
commit317c0644ccf108aa23ef3fd8358bd66c2840bfc0 (patch)
treec417b3d25c86b775989cb5ac042f37611b626c8a /deps/lua/test/factorial.lua
parentInitial commit. (diff)
downloadredis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.tar.xz
redis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.zip
Adding upstream version 5:7.2.4.upstream/5%7.2.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'deps/lua/test/factorial.lua')
-rw-r--r--deps/lua/test/factorial.lua32
1 files changed, 32 insertions, 0 deletions
diff --git a/deps/lua/test/factorial.lua b/deps/lua/test/factorial.lua
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+-- function closures are powerful
+
+-- traditional fixed-point operator from functional programming
+Y = function (g)
+ local a = function (f) return f(f) end
+ return a(function (f)
+ return g(function (x)
+ local c=f(f)
+ return c(x)
+ end)
+ end)
+end
+
+
+-- factorial without recursion
+F = function (f)
+ return function (n)
+ if n == 0 then return 1
+ else return n*f(n-1) end
+ end
+ end
+
+factorial = Y(F) -- factorial is the fixed point of F
+
+-- now test it
+function test(x)
+ io.write(x,"! = ",factorial(x),"\n")
+end
+
+for n=0,16 do
+ test(n)
+end