perf: use size hint when creating Chunk::Collect (#28)

Author: meskill

.gitignore

@@ -1 +1,3 @@
 /target
+
+.vscode

benches/operations.rs

@@ -1,6 +1,8 @@
 use criterion::{black_box, criterion_group, criterion_main, Criterion};
 use tailcall_chunk::Chunk;
 
+const N: usize = 10000;
+
 fn bench_operations(c: &mut Criterion) {
     // Benchmark append operations
     c.benchmark_group("append")
@@ -78,6 +80,13 @@ fn bench_operations(c: &mut Criterion) {
                 black_box(vec.clone());
             })
         });
+
+    // Benchmark from_iter operation
+    c.benchmark_group("from_iter")
+        .bench_function("Chunk", |b| {
+            b.iter(|| Chunk::from_iter((0..N).into_iter()));
+        })
+        .bench_function("Vec", |b| b.iter(|| Vec::from_iter((0..N).into_iter())));
 }
 
 criterion_group!(benches, bench_operations);

src/chunk.rs

@@ -349,11 +349,9 @@ impl<A> FromIterator<A> for Chunk<A> {
     /// assert_eq!(chunk.as_vec(), vec![1, 2, 3]);
     /// ```
     fn from_iter<T: IntoIterator<Item = A>>(iter: T) -> Self {
-        let mut chunk = Vec::default();
-        for item in iter {
-            chunk.push(item);
-        }
-        Chunk::Collect(Rc::new(RefCell::new(chunk)))
+        let vec: Vec<_> = iter.into_iter().collect();
+
+        Chunk::Collect(Rc::new(RefCell::new(vec)))
     }
 }