Rust: What is the difference between splice and insert?

splice — insert at range. insert — insert at index.

splice:

• Insert at range.
• Replace range.
• More flexible.

insert:

• Insert at index.
• Shift elements.
• Single position.

1let mut v = vec![1, 2, 3, 4, 5];
2v.splice(1..3, [10, 20]);
3// v: [1, 10, 20, 4, 5]
4
5let mut v = vec![1, 2, 3, 4, 5];
6v.insert(2, 10);
7// v: [1, 2, 10, 3, 4, 5]

Key: splice for range replacement, insert for single position.