expose traverse and traverse_result; tag 0.0.18

Author: tiye

Cargo.toml

@@ -1,7 +1,7 @@
 
 [package]
 name = "im_ternary_tree"
-version = "0.0.17"
+version = "0.0.18"
 edition = "2021"
 authors = ["jiyinyiyong <jiyinyiyong@gmail.com>"]
 license = "MIT"

benches/iterator.rs

@@ -1,5 +1,3 @@
-use std::cell::RefCell;
-
 use criterion::{criterion_group, criterion_main, Criterion};
 
 use im_ternary_tree::TernaryTreeList;
@@ -24,11 +22,11 @@ fn criterion_benchmark(c: &mut Criterion) {
   });
 
   c.bench_function("traverse", |b| {
-    let cc = RefCell::new(0);
+    let mut cc = 0;
 
     b.iter(|| {
-      data.traverse(|item| {
-        *cc.borrow_mut() += item;
+      data.traverse(&mut |item| {
+        cc += item;
       });
     })
   });

src/lib.rs

@@ -452,10 +452,19 @@ where
   }
 
   /// traverse all elements in list, use referenced value
-  pub fn traverse(&self, f: impl Fn(&T)) {
+  pub fn traverse(&self, f: &mut dyn FnMut(&T)) {
     match self {
       Empty => (),
-      Tree(t) => t.traverse(&f),
+      Tree(t) => t.traverse(f),
+    }
+  }
+
+  /// traverse elements in list, use referenced value,
+  /// returns `Ok` when all elements are traversed
+  pub fn traverse_result<S>(&self, f: &mut dyn FnMut(&T) -> Result<(), S>) -> Result<(), S> {
+    match self {
+      Empty => Ok(()),
+      Tree(t) => t.traverse_result(f),
     }
   }
 

src/tree.rs

@@ -1240,7 +1240,7 @@ where
     xs
   }
 
-  pub fn traverse(&self, f: &impl Fn(&T)) {
+  pub fn traverse(&self, f: &mut dyn FnMut(&T)) {
     match self {
       Leaf(value) => f(value),
       Branch2 { left, middle, .. } => {
@@ -1255,6 +1255,23 @@ where
     }
   }
 
+  pub fn traverse_result<S>(&self, f: &mut dyn FnMut(&T) -> Result<(), S>) -> Result<(), S> {
+    match self {
+      Leaf(value) => f(value),
+      Branch2 { left, middle, .. } => {
+        left.traverse_result(f)?;
+        middle.traverse_result(f)?;
+        Ok(())
+      }
+      Branch3 { left, middle, right, .. } => {
+        left.traverse_result(f)?;
+        middle.traverse_result(f)?;
+        right.traverse_result(f)?;
+        Ok(())
+      }
+    }
+  }
+
   pub fn iter(&self) -> TernaryTreeIterator<T> {
     TernaryTreeIterator {
       value: self,

tests/list_tests.rs

@@ -320,7 +320,7 @@ fn iterator() -> Result<(), String> {
 }
 
 #[test]
-fn traverse() -> Result<(), String> {
+fn iter_enum() -> Result<(), String> {
   let origin4 = [1, 2, 3, 4];
   let data4 = TernaryTreeList::from(&origin4);
 
@@ -483,3 +483,46 @@ fn split_values() -> Result<(), String> {
 
   Ok(())
 }
+
+#[test]
+fn traverse() -> Result<(), String> {
+  let n = 100;
+  let mut data = TernaryTreeList::from(&[]);
+  let mut total = 0;
+  for idx in 0..n {
+    data = data.append(idx);
+    total += idx;
+  }
+
+  let mut c = 0;
+
+  data.traverse(&mut |x| {
+    c += x;
+  });
+
+  assert_eq!(c, total);
+
+  Ok(())
+}
+
+#[test]
+fn traverse_result() -> Result<(), String> {
+  let n = 100;
+  let mut data = TernaryTreeList::from(&[]);
+  let mut total = 0;
+  for idx in 0..n {
+    data = data.append(idx);
+    total += idx;
+  }
+
+  let mut c = 0;
+
+  data.traverse_result::<String>(&mut |x| {
+    c += x;
+    Ok(())
+  })?;
+
+  assert_eq!(c, total);
+
+  Ok(())
+}