From 7ce7e24b887c9bc58feed78de302c6ce3dae20ab Mon Sep 17 00:00:00 2001
From: uri singer <urisig2007@gmail.com>
Date: Thu, 15 Aug 2024 11:30:28 +0300
Subject: [PATCH 1/2] prefix searches now use an iterator

---
 README.md               |  4 ++--
 src/iter/prefix_iter.rs | 27 +++++++++++++++------------
 src/map/trie.rs         | 23 ++++++++++++++---------
 src/trie/trie_impl.rs   | 32 +++++++++++++++++++++++---------
 4 files changed, 54 insertions(+), 32 deletions(-)

diff --git a/README.md b/README.md
index 00651c6..f091c22 100644
--- a/README.md
+++ b/README.md
@@ -64,8 +64,8 @@ assert_eq!(
 );
 
 // common_prefix_search(): Find words which is included in `query`'s prefix.
-let results_in_u8s: Vec<Vec<u8>> = trie.common_prefix_search("すしや").collect();
-let results_in_str: Vec<String> = trie.common_prefix_search("すしや").collect();
+let results_in_u8s: Vec<Vec<u8>> = trie.common_prefix_search("すしや".bytes()).collect();
+let results_in_str: Vec<String> = trie.common_prefix_search("すしや".bytes()).collect();
 assert_eq!(
     results_in_str,
     vec![
diff --git a/src/iter/prefix_iter.rs b/src/iter/prefix_iter.rs
index 1a0c897..db055ec 100644
--- a/src/iter/prefix_iter.rs
+++ b/src/iter/prefix_iter.rs
@@ -3,25 +3,28 @@ use crate::try_collect::{TryCollect, TryFromIterator};
 use louds_rs::LoudsNodeNum;
 use std::marker::PhantomData;
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 /// Iterates through all the common prefixes of a given query.
-pub struct PrefixIter<'a, Label, Value, C, M> {
+pub struct PrefixIter<'a, Label, I, Value, C, M> {
     trie: &'a Trie<Label, Value>,
-    query: Vec<Label>,
-    index: usize,
+    query: I,
     node: LoudsNodeNum,
     buffer: Vec<&'a Label>,
     consume: Option<&'a Value>,
     col: PhantomData<(C, M)>,
 }
 
-impl<'a, Label: Ord + Clone, Value, C, M> PrefixIter<'a, Label, Value, C, M> {
+impl<'a, 'b, Label: Ord + Clone, Value, I: Iterator<Item = Label>, C, M>
+    PrefixIter<'a, Label, I, Value, C, M>
+{
     #[inline]
-    pub(crate) fn new(trie: &'a Trie<Label, Value>, query: impl AsRef<[Label]>) -> Self {
+    pub(crate) fn new(
+        trie: &'a Trie<Label, Value>,
+        query: impl IntoIterator<IntoIter = I>,
+    ) -> Self {
         Self {
             trie,
-            query: query.as_ref().to_vec(),
-            index: 0,
+            query: query.into_iter(),
             node: LoudsNodeNum(1),
             buffer: Vec::new(),
             consume: None,
@@ -30,18 +33,19 @@ impl<'a, Label: Ord + Clone, Value, C, M> PrefixIter<'a, Label, Value, C, M> {
     }
 }
 
-impl<'a, Label: Ord + Clone, Value, C, M> Iterator for PrefixIter<'a, Label, Value, C, M>
+impl<'a, 'b, Label: Ord + Clone, Value, I: Iterator<Item = Label>, C, M> Iterator
+    for PrefixIter<'a, Label, I, Value, C, M>
 where
     C: TryFromIterator<Label, M>,
 {
     type Item = (C, &'a Value);
     fn next(&mut self) -> Option<Self::Item> {
         while self.consume.is_none() {
-            if let Some(chr) = self.query.get(self.index) {
+            if let Some(chr) = self.query.next() {
                 let children_node_nums: Vec<_> = self.trie.children_node_nums(self.node).collect();
                 let res = self
                     .trie
-                    .bin_search_by_children_labels(chr, &children_node_nums[..]);
+                    .bin_search_by_children_labels(&chr, &children_node_nums[..]);
                 match res {
                     Ok(j) => {
                         let child_node_num = children_node_nums[j];
@@ -54,7 +58,6 @@ where
             } else {
                 return None;
             }
-            self.index += 1;
         }
         if let Some(v) = self.consume.take() {
             let col = self.buffer.clone();
diff --git a/src/map/trie.rs b/src/map/trie.rs
index ee44b81..b18e1c8 100644
--- a/src/map/trie.rs
+++ b/src/map/trie.rs
@@ -53,12 +53,12 @@ impl<Label: Ord, Value> Trie<Label, Value> {
     ///
     /// Note: A prefix may be an exact match or not, and an exact match may be a
     /// prefix or not.
-    pub fn is_prefix(&self, query: impl AsRef<[Label]>) -> bool {
+    pub fn is_prefix(&self, query: impl IntoIterator<Item = Label>) -> bool {
         let mut cur_node_num = LoudsNodeNum(1);
 
-        for chr in query.as_ref().iter() {
+        for chr in query {
             let children_node_nums: Vec<_> = self.children_node_nums(cur_node_num).collect();
-            let res = self.bin_search_by_children_labels(chr, &children_node_nums[..]);
+            let res = self.bin_search_by_children_labels(&chr, &children_node_nums[..]);
             match res {
                 Ok(j) => cur_node_num = children_node_nums[j],
                 Err(_) => return false,
@@ -128,13 +128,14 @@ impl<Label: Ord, Value> Trie<Label, Value> {
     }
 
     /// Return the common prefixes of `query`.
-    pub fn common_prefix_search<C, M>(
+    pub fn common_prefix_search<'a, C, M, I>(
         &self,
-        query: impl AsRef<[Label]>,
-    ) -> PrefixIter<'_, Label, Value, C, M>
+        query: I,
+    ) -> PrefixIter<'_, Label, I::IntoIter, Value, C, M>
     where
         C: TryFromIterator<Label, M>,
         Label: Clone,
+        I: IntoIterator<Item = Label>,
     {
         PrefixIter::new(self, query)
     }
@@ -338,7 +339,11 @@ mod search_tests {
         assert!(trie.exact_match("").is_none());
         let _ = trie.predictive_search::<String, _>("").next();
         let _ = trie.postfix_search::<String, _>("").next();
-        let _ = trie.common_prefix_search::<String, _>("").next();
+
+        let trie2 = build_trie2();
+        let _ = trie2
+            .common_prefix_search::<String, _, _>(&mut "".chars())
+            .next();
     }
 
     #[test]
@@ -401,7 +406,7 @@ mod search_tests {
                 fn $name() {
                     let (query, expected_match) = $value;
                     let trie = super::build_trie();
-                    let result = trie.is_prefix(query);
+                    let result = trie.is_prefix(query.bytes());
                     assert_eq!(result, expected_match);
                 }
             )*
@@ -488,7 +493,7 @@ mod search_tests {
                 fn $name() {
                     let (query, expected_results) = $value;
                     let trie = super::build_trie();
-                    let results: Vec<(String, &u8)> = trie.common_prefix_search(query).collect();
+                    let results: Vec<(String, &u8)> = trie.common_prefix_search(&mut query.bytes()).collect();
                     let expected_results: Vec<(String, &u8)> = expected_results.iter().map(|s| (s.0.to_string(), &s.1)).collect();
                     assert_eq!(results, expected_results);
                 }
diff --git a/src/trie/trie_impl.rs b/src/trie/trie_impl.rs
index 1c82d98..a87a6b9 100644
--- a/src/trie/trie_impl.rs
+++ b/src/trie/trie_impl.rs
@@ -49,18 +49,19 @@ impl<Label: Ord> Trie<Label> {
     ///
     /// let trie = Trie::from_iter(["a", "app", "apple", "better", "application"]);
     ///
-    /// let results: Vec<String> = trie.common_prefix_search("application").collect();
+    /// let results: Vec<String> = trie.common_prefix_search("application".bytes()).collect();
     ///
     /// assert_eq!(results, vec!["a", "app", "application"]);
     ///
     /// ```
-    pub fn common_prefix_search<C, M>(
+    pub fn common_prefix_search<C, M, I>(
         &self,
-        query: impl AsRef<[Label]>,
-    ) -> Keys<PrefixIter<'_, Label, (), C, M>>
+        query: I,
+    ) -> Keys<PrefixIter<'_, Label, I::IntoIter, (), C, M>>
     where
         C: TryFromIterator<Label, M>,
         Label: Clone,
+        I: IntoIterator<Item = Label>,
     {
         // TODO: We could return Keys iterators instead of collecting.
         self.0.common_prefix_search(query).keys()
@@ -146,7 +147,7 @@ impl<Label: Ord> Trie<Label> {
     ///
     /// Note: A prefix may be an exact match or not, and an exact match may be a
     /// prefix or not.
-    pub fn is_prefix(&self, query: impl AsRef<[Label]>) -> bool {
+    pub fn is_prefix(&self, query: impl IntoIterator<Item = Label>) -> bool {
         self.0.is_prefix(query)
     }
 
@@ -194,6 +195,17 @@ mod search_tests {
         builder.build()
     }
 
+    fn build_trie2() -> Trie<char> {
+        let mut builder = TrieBuilder::new();
+        builder.insert("a".chars());
+        builder.insert("app".chars());
+        builder.insert("apple".chars());
+        builder.insert("better".chars());
+        builder.insert("application".chars());
+        builder.insert("アップル🍎".chars());
+        builder.build()
+    }
+
     #[test]
     fn trie_from_iter() {
         let trie = Trie::<u8>::from_iter(["a", "app", "apple", "better", "application"]);
@@ -240,7 +252,9 @@ mod search_tests {
         assert!(!trie.exact_match(""));
         let _ = trie.predictive_search::<String, _>("").next();
         let _ = trie.postfix_search::<String, _>("").next();
-        let _ = trie.common_prefix_search::<String, _>("").next();
+        let _ = trie
+            .common_prefix_search::<String, _, _>(&mut "".bytes())
+            .next();
     }
 
     #[cfg(feature = "mem_dbg")]
@@ -322,7 +336,7 @@ mod search_tests {
                 fn $name() {
                     let (query, expected_match) = $value;
                     let trie = super::build_trie();
-                    let result = trie.is_prefix(query);
+                    let result = trie.is_prefix(query.bytes());
                     assert_eq!(result, expected_match);
                 }
             )*
@@ -378,8 +392,8 @@ mod search_tests {
                 #[test]
                 fn $name() {
                     let (query, expected_results) = $value;
-                    let trie = super::build_trie();
-                    let results: Vec<String> = trie.common_prefix_search(query).collect();
+                    let trie = super::build_trie2();
+                    let results: Vec<String> = trie.common_prefix_search(&mut query.chars()).collect();
                     assert_eq!(results, expected_results);
                 }
             )*

From d3fd2799f4e07629fa1451b6c5ce1927029bfda5 Mon Sep 17 00:00:00 2001
From: uri singer <urisig2007@gmail.com>
Date: Thu, 15 Aug 2024 21:21:51 +0300
Subject: [PATCH 2/2] fix benches

---
 benches/bench.rs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/benches/bench.rs b/benches/bench.rs
index 1f47f75..9ef5150 100644
--- a/benches/bench.rs
+++ b/benches/bench.rs
@@ -219,9 +219,9 @@ mod trie {
                         // Tested function takes too short compared to build().
                         // So loop many times.
                         let results_in_str: Vec<String> =
-                            trie.common_prefix_search("すしをにぎる").collect();
+                            trie.common_prefix_search("すしをにぎる".bytes()).collect();
                         for _ in 0..(times - 1) {
-                            for entry in trie.common_prefix_search("すしをにぎる") {
+                            for entry in trie.common_prefix_search("すしをにぎる".bytes()) {
                                 black_box::<Vec<u8>>(entry);
                             }
                         }
@@ -249,12 +249,12 @@ mod trie {
                         // iter_batched() does not properly time `routine` time when `setup` time is far longer than `routine` time.
                         // Tested function takes too short compared to build(). So loop many times.
                         let result = trie
-                            .common_prefix_search::<Vec<u8>, _>("すしをにぎる")
+                            .common_prefix_search::<Vec<u8>, _, _>("すしをにぎる".bytes())
                             .next()
                             .is_some();
                         for _ in 0..(times - 1) {
                             let _ = trie
-                                .common_prefix_search::<Vec<u8>, _>("すしをにぎる")
+                                .common_prefix_search::<Vec<u8>, _, _>("すしをにぎる".bytes())
                                 .next()
                                 .is_some();
                         }