remove clone from into_iter

saphyr/src/yaml.rs

@@ -344,22 +344,21 @@ impl IntoIterator for Yaml {
     type IntoIter = YamlIter;
 
     fn into_iter(self) -> Self::IntoIter {
-        YamlIter {yaml: self, index: 0}
+        let mut yaml = self.into_vec().unwrap_or(vec![]);
+        yaml.reverse();
+        YamlIter {yaml: yaml}
     }
 }
 
 pub struct YamlIter {
-    yaml: Yaml,
-    index: usize,
+    yaml: Vec<Yaml>,
 }
 
 impl Iterator for YamlIter {
     type Item = Yaml;
 
     fn next(&mut self) -> Option<Yaml> {
-        let result = self.yaml[self.index].clone();
-        self.index += 1;
-        Some(result)
+        self.yaml.pop()
     }
 }