1. 赋值: 多重赋值, 赋值过程中一一对应
a, b = x, y
a = b, b = y
交换变量 x, y = y, x
2. 局部变量与块
local 定义一个局部变量
3. 控制结构
if a == b then
r = a + b
elseif a > b then
r = a - b
else
r = a / b
end
local i = 1
while a[i] do
print(a[i])
i = i + 1
end
repeat
line = io.read()
until line ~= ""
for i=1, #a do
if a[i] < 0 then
found = 1
break
end
end