Lua 是没有 continue 关键字的，Lua 的作者 Roberto 在 mail list 提到过原因：
Continue, on the other hand, is a real feature. (It even changes the
syntax and the lexical.) Our main concern with "continue" is that there
are several other control structures that (in our view) are more or
less as important as "continue" and may even replace it. (E.g., break
with labels [as in Java] or even a more generic goto.) "continue" does
not seem more special than other control-structure mechanisms, except
that it is present in more languages. (Perl actually has two "continue"
statements, "next" and "redo". Both are useful.)
有时候业务需要，就不得不靠我们自己去实现了。先来一个递归版本：
local function foo(i, max)
if i == 5 then
return foo(6, max) -- continue to i=6
end
print(i)
if i == max then
return
else
return foo(i+1, max)
end
end
foo(1, 10)
优点是逻辑简单明了，缺点就是递归导致的栈溢出问题。再来一个性能优化的版本，也就是再套一层循环：
for i = 1,10 do
-- 这个 repeat 循环在每个 for 循环下只会跑一次
repeat
-- 这个 break 跳出 repeat 循环，相当于 continue 的效果
if i == 5 then break end
print(i)
until true
end
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