example

for 语法

语法	等价于	访问级别
for item in collection	for item in IntoIterator::into_iter(collection)	拥有所有权,也就是for语句结束之后，collection已经无效
for item in &collection	for item in collection.iter()	只读，语句结束，collection有效
for item in &mut collection	for item in collection.iter_mut()	读写，语句结束，collection有效