/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// for key in map.keys() {
/// println!("{}", key);
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// for val in map.values() {
/// println!("{}", val);
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- ///
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let mut map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// for val in map.values_mut() {
/// *val = *val + 10;
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// for (key, val) in map.iter() {
/// println!("key: {} val: {}", key, val);
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let mut map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// // Update all values
/// for (_, val) in map.iter_mut() {
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// let mut vec: Vec<&str> = map.into_keys().collect();
/// // The `IntoKeys` iterator produces keys in arbitrary order, so the
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// let mut vec: Vec<i32> = map.into_values().collect();
/// // The `IntoValues` iterator produces values in arbitrary order, so
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter = map.iter();
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let mut map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter = map.iter_mut();
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter = map.into_iter();
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter_keys = map.keys();
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter_values = map.values();
/// ```
#[stable(feature = "rust1", since = "1.0.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let mut map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter = map.drain();
/// ```
#[stable(feature = "drain", since = "1.6.0")]
///
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let mut map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter = map.drain_filter(|_k, v| *v % 2 == 0);
/// ```
#[unstable(feature = "hash_drain_filter", issue = "59618")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let mut map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter_values = map.values_mut();
/// ```
#[stable(feature = "map_values_mut", since = "1.10.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter_keys = map.into_keys();
/// ```
#[stable(feature = "map_into_keys_values", since = "1.54.0")]
/// ```
/// use std::collections::HashMap;
///
-/// let mut map = HashMap::new();
-/// map.insert("a", 1);
+/// let map = HashMap::from([
+/// ("a", 1),
+/// ]);
/// let iter_keys = map.into_values();
/// ```
#[stable(feature = "map_into_keys_values", since = "1.54.0")]
/// ```
/// use std::collections::HashMap;
///
- /// let mut map = HashMap::new();
- /// map.insert("a", 1);
- /// map.insert("b", 2);
- /// map.insert("c", 3);
+ /// let map = HashMap::from([
+ /// ("a", 1),
+ /// ("b", 2),
+ /// ("c", 3),
+ /// ]);
///
/// // Not possible with .iter()
/// let vec: Vec<(&str, i32)> = map.into_iter().collect();