for

The for loop iterates over ranges of values or the items in a collection:

1. fn main() {
2. for x in 1..5 {
3. println!("x: {x}");
4. }

6. for elem in [1, 2, 3, 4, 5] {
7. println!("elem: {elem}");
8. }
9. }

• Under the hood for loops use a concept called “iterators” to handle iterating over different kinds of ranges/collections. Iterators will be discussed in more detail later.
• 请注意，for 循环只迭代到 4。现在展示使用 1..=5 语法表示一个包含边界的范围。