Switch to iterators

src/lib.rs

@@ -55,25 +55,23 @@
 ///    }
 /// }
 ///
-/// fn main() {
 ///
-///    let table = vec![MyPair{ a: 10, b:34}, MyPair{ a: 1, b:56}, MyPair{ a: 2, b:23}];
+/// let table = vec![MyPair{ a: 10, b:34}, MyPair{ a: 1, b:56}, MyPair{ a: 2, b:23}];
 ///
-///    // Example without using an actual index crate, we will simply use
+/// // Example without using an actual index crate, we will simply use
-///    // the Record<K> trait to sort the array of pairs.
+/// // the Record<K> trait to sort the array of pairs.
-///    let mut lex_sort = table.clone();
+/// let mut lex_sort = table.clone();
-///    lex_sort.sort_unstable_by_key(|e| {let k: String = e.key(); k});
+/// lex_sort.sort_unstable_by_key(|e| {let k: String = e.key(); k});
 ///
-///    let mut num_sort = table.clone();
+/// let mut num_sort = table.clone();
-///    num_sort.sort_unstable_by_key(|e| {let k: i64 = e.key(); k});
+/// num_sort.sort_unstable_by_key(|e| {let k: i64 = e.key(); k});
 ///
-///    assert_eq!(format!("unsorted {:?}", table),
+/// assert_eq!(format!("unsorted {:?}", table),
-///         "unsorted [MyPair { a: 10, b: 34 }, MyPair { a: 1, b: 56 }, MyPair { a: 2, b: 23 }]");
+///      "unsorted [MyPair { a: 10, b: 34 }, MyPair { a: 1, b: 56 }, MyPair { a: 2, b: 23 }]");
-///    assert_eq!(format!("lex sort {:?}", lex_sort),
+/// assert_eq!(format!("lex sort {:?}", lex_sort),
-///         "lex sort [MyPair { a: 1, b: 56 }, MyPair { a: 10, b: 34 }, MyPair { a: 2, b: 23 }]");
+///      "lex sort [MyPair { a: 1, b: 56 }, MyPair { a: 10, b: 34 }, MyPair { a: 2, b: 23 }]");
-///    assert_eq!(format!("num sort {:?}", num_sort),
+/// assert_eq!(format!("num sort {:?}", num_sort),
-///         "num sort [MyPair { a: 1, b: 56 }, MyPair { a: 2, b: 23 }, MyPair { a: 10, b: 34 }]");
+///      "num sort [MyPair { a: 1, b: 56 }, MyPair { a: 2, b: 23 }, MyPair { a: 10, b: 34 }]");
-/// }
 /// ```
 pub trait Record<K> {
     /// Extract the key from the record.
@@ -104,14 +102,14 @@ pub trait RecordFields<F> {
 // semantic order
 pub trait Indexed<R, K> {
     /// Retrieve all records matching the key.
-    fn find(&self, key: &K) -> Vec<&R>;
+    fn find<'i>(&'i self, key: &K) -> Box<dyn Iterator<Item = &R> + 'i>;
 
     /// Retrieve all records matching in the key range defined by
     /// `start` and `end`.
     ///
     /// * `start` is included
     // TODO: TBC for `end`
-    fn find_range(&self, start: &K, end: &K) -> Vec<&R>;
+    fn find_range<'i>(&'i self, start: &K, end: &K) -> Box<dyn Iterator<Item = &R> + 'i>;
 }
 
 /// Methods provided by destructuring indices.
@@ -123,12 +121,12 @@ pub trait Indexed<R, K> {
 ///  * `K`: Type of the keys
 pub trait IndexedDestructured<F, K> {
     /// Retrieve all records matching the key.
-    fn find(&self, key: &K) -> Vec<&F>;
+    fn find<'i>(&'i self, key: &K) -> Box<dyn Iterator<Item = &F> + 'i>;
 
     /// Retrieve all records matching in the key range defined by
     /// `start` and `end`.
     ///
     /// * `start` is included
     // TODO: TBC for `end`
-    fn find_range(&self, start: &K, end: &K) -> Vec<(K, &F)>;
+    fn find_range<'i>(&'i self, start: &K, end: &K) -> Box<dyn Iterator<Item = (K, &F)> + 'i>;
 }