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+## Concise Control Flow with `if let`
+
+The `if let` syntax lets you combine `if` and `let` into a less verbose way to
+handle values that match one pattern while ignoring the rest. Consider the
+program in Listing 6-6 that matches on an `Option<u8>` value in the `config_max`
+variable but only wants to execute code if the value is the `Some` variant.
+
+```rust
+{{#rustdoc_include ../listings/ch06-enums-and-pattern-matching/listing-06-06/src/main.rs:here}}
+```
+
+<span class="caption">Listing 6-6: A `match` that only cares about executing
+code when the value is `Some`</span>
+
+If the value is `Some`, we print out the value in the `Some` variant by binding
+the value to the variable `max` in the pattern. We don’t want to do anything
+with the `None` value. To satisfy the `match` expression, we have to add `_ =>
+()` after processing just one variant, which is annoying boilerplate code to
+add.
+
+Instead, we could write this in a shorter way using `if let`. The following
+code behaves the same as the `match` in Listing 6-6:
+
+```rust
+{{#rustdoc_include ../listings/ch06-enums-and-pattern-matching/no-listing-12-if-let/src/main.rs:here}}
+```
+
+The syntax `if let` takes a pattern and an expression separated by an equal
+sign. It works the same way as a `match`, where the expression is given to the
+`match` and the pattern is its first arm. In this case, the pattern is
+`Some(max)`, and the `max` binds to the value inside the `Some`. We can then
+use `max` in the body of the `if let` block in the same way as we used `max` in
+the corresponding `match` arm. The code in the `if let` block isn’t run if the
+value doesn’t match the pattern.
+
+Using `if let` means less typing, less indentation, and less boilerplate code.
+However, you lose the exhaustive checking that `match` enforces. Choosing
+between `match` and `if let` depends on what you’re doing in your particular
+situation and whether gaining conciseness is an appropriate trade-off for
+losing exhaustive checking.
+
+In other words, you can think of `if let` as syntax sugar for a `match` that
+runs code when the value matches one pattern and then ignores all other values.
+
+We can include an `else` with an `if let`. The block of code that goes with the
+`else` is the same as the block of code that would go with the `_` case in the
+`match` expression that is equivalent to the `if let` and `else`. Recall the
+`Coin` enum definition in Listing 6-4, where the `Quarter` variant also held a
+`UsState` value. If we wanted to count all non-quarter coins we see while also
+announcing the state of the quarters, we could do that with a `match`
+expression like this:
+
+```rust
+{{#rustdoc_include ../listings/ch06-enums-and-pattern-matching/no-listing-13-count-and-announce-match/src/main.rs:here}}
+```
+
+Or we could use an `if let` and `else` expression like this:
+
+```rust
+{{#rustdoc_include ../listings/ch06-enums-and-pattern-matching/no-listing-14-count-and-announce-if-let-else/src/main.rs:here}}
+```
+
+If you have a situation in which your program has logic that is too verbose to
+express using a `match`, remember that `if let` is in your Rust toolbox as well.
+
+## Summary
+
+We’ve now covered how to use enums to create custom types that can be one of a
+set of enumerated values. We’ve shown how the standard library’s `Option<T>`
+type helps you use the type system to prevent errors. When enum values have
+data inside them, you can use `match` or `if let` to extract and use those
+values, depending on how many cases you need to handle.
+
+Your Rust programs can now express concepts in your domain using structs and
+enums. Creating custom types to use in your API ensures type safety: the
+compiler will make certain your functions get only values of the type each
+function expects.
+
+In order to provide a well-organized API to your users that is straightforward
+to use and only exposes exactly what your users will need, let’s now turn to
+Rust’s modules.