ucarion · December 22, 2014 23:37 · Dec 22, 2014
diff --git a/each_cons.rs b/each_cons.rs
@@ -0,0 +1,43 @@
+#![feature(slicing_syntax)]
+
+use std::collections::RingBuf;
+
+fn main() {
+    let xs = &[1i, 2i, 3i, 4i, 5i];
+    let mut iter = EachCons { iter: xs.iter(), n: 3, buffer: RingBuf::new() };
+
+    for x in iter {
+        println!("{}", x);
+    }
+}
+
+pub struct EachCons<A, T> where T: Iterator<A> {
+    iter: T,
+    n: uint,
+    buffer: RingBuf<A>
+}
+
+impl<A: Clone, T: Iterator<A>> Iterator<Vec<A>> for EachCons<A, T> {
+    fn next(&mut self) -> Option<Vec<A>> {
+        for x in self.iter {
+            self.buffer.push_back(x);
+
+            if self.buffer.len() > self.n {
+                self.buffer.pop_front();
+            }
+
+            if self.buffer.len() == self.n {
+                let (slice, _) = self.buffer.as_slices();
+
+                let mut v = Vec::new();
+                v.push_all(slice);
+
+                return Some(v);
+            } else {
+                continue
+            }
+        }
+
+        None
+    }
+}