理解Lua的Coroutine

co01=coroutine.create(function(a) return 2*a end)
a,b=coroutine.resume(co01,20)
print(a,b)
co02=coroutine.wrap(function(a) return 2*a end)
c=co02(20)
print(c)

print("==========分割线===========")
co = coroutine.wrap(function(a)
local c = coroutine.yield(a+1)
print("main func a: ",a)
return 2*a
end)
b = co(20)
print(b) -- 21
--从yield后面执行
d = co(b+1)
print(d) -- 40
print("==========分割线===========")
co = coroutine.create(function(a) local c = coroutine.yield(a+1) print("main func c: ",c) return 2*a end)
b,v = coroutine.resume(co,20)
print(b,v) -- true，21
b,v = coroutine.resume(co,20)
print(b,v) -- true,40