minix/external/mit/lua/dist/test/sieve.lua
Lionel Sambuc 11be35a165 Importing NetBSD "Kyua" test framework
To do so, a few dependencies have been imported:

 * external/bsd/lutok
 * external/mit/lua
 * external/public-domain/sqlite
 * external/public-domain/xz

The Kyua framework is the new generation of ATF (Automated Test
Framework), it is composed of:

 * external/bsd/atf
 * external/bsd/kyua-atf-compat
 * external/bsd/kyua-cli
 * external/bsd/kyua-tester
 * tests

Kyua/ATF being written in C++, it depends on libstdc++ which is
provided by GCC. As this is not part of the sources, Kyua is only
compiled when the native GCC utils are installed.

To install Kyua do the following:

 * In a cross-build enviromnent, add the following to the build.sh
   commandline: -V MKBINUTILS=yes -V MKGCCCMDS=yes

WARNING:
  At this point the import is still experimental, and not supported
  on native builds (a.k.a make build).

Change-Id: I26aee23c5bbd2d64adcb7c1beb98fe0d479d7ada
2013-07-23 20:43:41 +02:00

29 lines
774 B
Lua

-- the sieve of of Eratosthenes programmed with coroutines
-- typical usage: lua -e N=1000 sieve.lua | column
-- generate all the numbers from 2 to n
function gen (n)
return coroutine.wrap(function ()
for i=2,n do coroutine.yield(i) end
end)
end
-- filter the numbers generated by `g', removing multiples of `p'
function filter (p, g)
return coroutine.wrap(function ()
while 1 do
local n = g()
if n == nil then return end
if math.mod(n, p) ~= 0 then coroutine.yield(n) end
end
end)
end
N=N or 1000 -- from command line
x = gen(N) -- generate primes up to N
while 1 do
local n = x() -- pick a number until done
if n == nil then break end
print(n) -- must be a prime number
x = filter(n, x) -- now remove its multiples
end