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Indent code in speaker notes (#476)

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* Indent code in speaker notes

#475

* Update stack.md

* Update destructuring-arrays.md

* Update hashmap.md

* Update traits.md
This commit is contained in:
Charisee Chiw
2023-03-11 14:12:32 -08:00
committed by GitHub
parent 368f3ba302
commit 59d3d7f625
5 changed files with 121 additions and 122 deletions
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src/std/hashmap.md
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@ -38,23 +38,23 @@ fn main() {
* `HashMap` is not defined in the prelude and needs to be brought into scope.
* Try the following lines of code. The first line will see if a book is in the hashmap and if not return an alternative value. The second line will insert the alternative value in the hashmap if the book is not found.
```rust,ignore
let pc1 = page_counts
.get("Harry Potter and the Sorcerer's Stone ")
.unwrap_or(&336);
let pc2 = page_counts
.entry("The Hunger Games".to_string())
.or_insert(374);
```
```rust,ignore
let pc1 = page_counts
.get("Harry Potter and the Sorcerer's Stone ")
.unwrap_or(&336);
let pc2 = page_counts
.entry("The Hunger Games".to_string())
.or_insert(374);
```
* Unlike `vec!`, there is unfortunately no standard `hashmap!` macro.
* Although, since Rust 1.56, HashMap implements [`From<[(K, V); N]>`][1], which allows us to easily initialize a hash map from a literal array:
```rust,ignore
let page_counts = HashMap::from([
("Harry Potter and the Sorcerer's Stone".to_string(), 336),
("The Hunger Games".to_string(), 374),
]);
```
```rust,ignore
let page_counts = HashMap::from([
("Harry Potter and the Sorcerer's Stone".to_string(), 336),
("The Hunger Games".to_string(), 374),
]);
```
* Alternatively HashMap can be built from any `Iterator` which yields key-value tuples.
* We are showing `HashMap<String, i32>`, and avoid using `&str` as key to make examples easier. Using references in collections can, of course, be done,