Lua 5.3 迭代器的简单示例
Lua 5.3 迭代器的简单示例
创建”closure”模式的”iterator”
function allowrds() local line = io.read() local pos = 1 return function () while line do local s, e = string.find(line, "%w+", pos) if s then pos = e + 1 return string.sub(line, s, e) else line = io.read() pos = 1 end end return nil end end for word in allowrds() do print(word) end
结果运行现象:
创建”complex state iterator”模式的”iterator”
function iter(state) while state.line do local s, e = string.find(state.line, "%w+", state.pos) if s then state.pos = e + 1 return string.sub(state.line, s, e) else state.line = io.read() state.pos = 1 end end return nil end function allowrds() local state = {line = io.read(), pos = 1} return iter, state end for word in allowrds() do print(word) end
结果运行现象: