Rust 1.82.0
f6e511eec

if let

There is a new edition of the book and this is an old link.

The if let syntax lets you combine if and let into a less verbose way to handle values that match one pattern and ignore the rest.

let some_u8_value = Some(3u8);
if let Some(3) = some_u8_value {
    println!("three");
}

Here are the relevant sections in the new and old books:

• In the current edition: Ch 6.03 — Concise Control Flow with if let
• In the first edition: Ch 3.21 — if let