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1.3: 更新文档, 增加更真实的样例
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‎README-CN.md‎

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@@ -251,3 +251,127 @@ hash_map! : insert() 添加键值对
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b_tree_map! : insert() 添加键值对
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b_tree_set! : insert() 添加元素
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# 一些实际的例子
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```rust
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// 创建3x3矩阵
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let matrix = vector![
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vector![i * 3 + j + 1 for j in 0..3]
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for i in 0..3
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];
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// 矩阵转置
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let transposed = vector![
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vector![row[i]
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for row in matrix.iter()]
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for i in 0..3
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];
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// matrix is alive
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assert_eq!(matrix, vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]]);
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assert_eq!(
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transposed,
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vec![vec![1, 4, 7], vec![2, 5, 8], vec![3, 6, 9]]
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);
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```
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```rust
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#[derive(Debug, PartialEq, Eq)]
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struct Score {
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subject: &'static str,
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score: u8,
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}
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#[derive(Debug, PartialEq, Eq)]
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struct Student {
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name: String,
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age: u8,
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scores: Vec<Score>,
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}
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let students_data = [
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Student {
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name: "Alice".to_string(),
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age: 20,
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scores: vec![
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Score {
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subject: "Math",
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score: 95,
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},
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Score {
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subject: "English",
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score: 88,
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},
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],
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},
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Student {
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name: "Bob".to_string(),
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age: 21,
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scores: vec![
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Score {
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subject: "Math",
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score: 78,
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},
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Score {
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subject: "English",
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score: 85,
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},
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],
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},
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];
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// use for loop
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let math_scores: HashMap<&String, u8> = {
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let mut math_scores = HashMap::new();
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for student in &students_data {
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for score in &student.scores {
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if score.subject == "Math" {
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math_scores.insert(&student.name, score.score);
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}
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}
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}
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math_scores
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};
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// ↓ 等价于 ↓
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// use comprehension!
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let math_scores: HashMap<&String, u8> = hash_map![
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&student.name => score.score
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for student in &students_data
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for score in &student.scores if score.subject == "Math"
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];
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assert_eq!(
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math_scores,
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HashMap::from([(&"Alice".to_string(), 95), (&"Bob".to_string(), 78)])
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);
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// use for loop
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let high_scores = {
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let mut high_scores = BTreeMap::new();
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for student in &students_data {
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let mut subjects = Vec::new();
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for score in &student.scores {
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if score.score >= 85 {
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subjects.push(score.subject);
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}
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}
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high_scores.insert(&student.name, subjects);
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}
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high_scores
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};
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// ↓ 等价于 ↓
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// use comprehension!
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let high_scores = b_tree_map![
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&student.name =>
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vector![score.subject for score in &student.scores if score.score >= 85]
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for student in &students_data
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];
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assert_eq!(
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high_scores,
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BTreeMap::from([
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(&"Alice".to_string(), vec!["Math", "English"]),
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(&"Bob".to_string(), vec!["English"])
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])
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);
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```

‎README.md‎

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@@ -261,3 +261,128 @@ b_tree_set! : insert() to add elements
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hash_map! : insert() to add key-value pairs
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b_tree_map! : insert() to add key-value pairs
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# some real examples
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```rust
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// create a 3x3 matrix
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let matrix = vector![
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vector![i * 3 + j + 1 for j in 0..3]
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for i in 0..3
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];
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// transpose the matrix
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let transposed = vector![
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vector![row[i]
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for row in matrix.iter()]
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for i in 0..3
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];
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// matrix is alive
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assert_eq!(matrix, vec![vec![1, 2, 3], vec![4, 5, 6], vec![7, 8, 9]]);
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assert_eq!(
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transposed,
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vec![vec![1, 4, 7], vec![2, 5, 8], vec![3, 6, 9]]
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);
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```
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```rust
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#[derive(Debug, PartialEq, Eq)]
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struct Score {
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subject: &'static str,
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score: u8,
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}
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#[derive(Debug, PartialEq, Eq)]
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struct Student {
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name: String,
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age: u8,
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scores: Vec<Score>,
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}
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let students_data = [
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Student {
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name: "Alice".to_string(),
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age: 20,
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scores: vec![
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Score {
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subject: "Math",
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score: 95,
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},
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Score {
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subject: "English",
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score: 88,
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},
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],
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},
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Student {
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name: "Bob".to_string(),
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age: 21,
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scores: vec![
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Score {
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subject: "Math",
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score: 78,
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},
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Score {
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subject: "English",
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score: 85,
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},
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],
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},
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];
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// use for loop
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let math_scores: HashMap<&String, u8> = {
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let mut math_scores = HashMap::new();
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for student in &students_data {
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for score in &student.scores {
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if score.subject == "Math" {
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math_scores.insert(&student.name, score.score);
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}
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}
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}
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math_scores
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};
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// ↓ is equivalent to ↓
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// use comprehension!
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let math_scores: HashMap<&String, u8> = hash_map![
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&student.name => score.score
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for student in &students_data
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for score in &student.scores if score.subject == "Math"
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];
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assert_eq!(
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math_scores,
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HashMap::from([(&"Alice".to_string(), 95), (&"Bob".to_string(), 78)])
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);
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// use for loop
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let high_scores = {
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let mut high_scores = BTreeMap::new();
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for student in &students_data {
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let mut subjects = Vec::new();
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for score in &student.scores {
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if score.score >= 85 {
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subjects.push(score.subject);
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}
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}
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high_scores.insert(&student.name, subjects);
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}
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high_scores
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};
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// ↓ is equivalent to ↓
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// use comprehension!
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let high_scores = b_tree_map![
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&student.name =>
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vector![score.subject for score in &student.scores if score.score >= 85]
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for student in &students_data
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];
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assert_eq!(
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high_scores,
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BTreeMap::from([
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(&"Alice".to_string(), vec!["Math", "English"]),
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(&"Bob".to_string(), vec!["English"])
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])
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);
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```

‎src/lib.rs‎

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@@ -270,6 +270,138 @@
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//! hash_map! : insert() to add key-value pairs
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//!
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//! b_tree_map! : insert() to add key-value pairs
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//!
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//! # some real examples
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//!
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//! ```rust
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//! use better_comprehension::vector;
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//! use std::collections::{HashMap, BTreeMap};
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//! // create a 3x3 matrix
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//! let matrix = vector![
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//! vector![i * 3 + j + 1 for j in 0..3]
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//! for i in 0..3
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//! ];
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//!
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//! // transpose the matrix
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//! let transposed = vector![
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//! vector![row[i]
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//! for row in matrix.iter()]
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//! for i in 0..3
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//! ];
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//! // matrix is alive
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//! assert_eq!(matrix, vec![vec![1, 2, 3],
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//! vec![4, 5, 6],
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//! vec![7, 8, 9]]);
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//! assert_eq!(
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//! transposed,
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//! vec![vec![1, 4, 7],
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//! vec![2, 5, 8],
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//! vec![3, 6, 9]]
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//! );
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//! ```
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//!
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//! ```rust
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//! use better_comprehension::{hash_map, b_tree_map, vector};
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//! use std::collections::{HashMap, BTreeMap};
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//! #[derive(Debug, PartialEq, Eq)]
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//! struct Score {
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//! subject: &'static str,
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//! score: u8,
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//! }
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//! #[derive(Debug, PartialEq, Eq)]
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//! struct Student {
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//! name: String,
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//! age: u8,
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//! scores: Vec<Score>,
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//! }
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//!
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//! let students_data = [
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//! Student {
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//! name: "Alice".to_string(),
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//! age: 20,
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//! scores: vec![
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//! Score {
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//! subject: "Math",
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//! score: 95,
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//! },
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//! Score {
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//! subject: "English",
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//! score: 88,
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//! },
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//! ],
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//! },
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//! Student {
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//! name: "Bob".to_string(),
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//! age: 21,
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//! scores: vec![
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//! Score {
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//! subject: "Math",
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//! score: 78,
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//! },
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//! Score {
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//! subject: "English",
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//! score: 85,
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//! },
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//! ],
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//! },
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//! ];
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//!
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//! // use for loop
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//! let math_scores: HashMap<&String, u8> = {
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//! let mut math_scores = HashMap::new();
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//! for student in &students_data {
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//! for score in &student.scores {
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//! if score.subject == "Math" {
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//! math_scores.insert(&student.name, score.score);
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//! }
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//! }
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//! }
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//! math_scores
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//! };
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//! // ↓ is equivalent to ↓
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//! // use comprehension!
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//! let math_scores: HashMap<&String, u8> = hash_map![
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//! &student.name => score.score
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//! for student in &students_data
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//! for score in &student.scores if score.subject == "Math"
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//! ];
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//!
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//! assert_eq!(
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//! math_scores,
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//! HashMap::from([(&"Alice".to_string(), 95),
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//! (&"Bob".to_string(), 78)]));
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//!
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//! // use for loop
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//! let high_scores = {
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//! let mut high_scores = BTreeMap::new();
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//! for student in &students_data {
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//! let mut subjects = Vec::new();
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//! for score in &student.scores {
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//! if score.score >= 85 {
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//! subjects.push(score.subject);
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//! }
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//! }
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//! high_scores.insert(&student.name, subjects);
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//! }
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//! high_scores
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//! };
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//! // ↓ is equivalent to ↓
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//! // use comprehension!
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//! let high_scores = b_tree_map![
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//! &student.name =>
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//! vector![score.subject
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//! for score in &student.scores if score.score >= 85]
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//! for student in &students_data
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//! ];
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//!
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//! assert_eq!(
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//! high_scores,
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//! BTreeMap::from([
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//! (&"Alice".to_string(), vec!["Math", "English"]),
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//! (&"Bob".to_string(), vec!["English"])
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//! ])
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//! );
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//! ```
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// #![allow(unused, dead_code)]
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use proc_macro::TokenStream as TS;

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