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+# Using `#[derive(IntoIterator)]`
+
+Deriving `IntoIterator` only works for a single field of a struct.
+The result is that you will call `.into_iter()` on this field directly.
+
+With `#[into_iterator]` or `#[into_iterator(ignore)]` it's possible to indicate
+the field that you want to derive `IntoIterator` for.
+
+By using `#[into_iterator(owned, ref, ref_mut)]` it's possible to derive an
+`IntoIterator` implementation for reference types as well.
+You can pick any combination of `owned`, `ref` and `ref_mut`.
+If that's not provided the default is `#[IntoIterator(owned)]`.
+
+
+
+
+## Example usage
+
+```rust
+# use derive_more::IntoIterator;
+#
+#[derive(IntoIterator)]
+struct MyVec(Vec<i32>);
+
+// You can specify the field you want to derive `IntoIterator` for
+#[derive(IntoIterator)]
+struct Numbers {
+    #[into_iterator(owned, ref,  ref_mut)]
+    numbers: Vec<i32>,
+    useless: bool,
+}
+
+assert_eq!(Some(5), MyVec(vec![5, 8]).into_iter().next());
+
+let mut nums = Numbers{numbers: vec![100, 200], useless: false};
+assert_eq!(Some(&100), (&nums).into_iter().next());
+assert_eq!(Some(&mut 100), (&mut nums).into_iter().next());
+assert_eq!(Some(100), nums.into_iter().next());
+```
+
+
+
+
+## Structs
+
+When deriving `IntoIterator` for a struct:
+
+```rust
+# use derive_more::IntoIterator;
+#
+#[derive(IntoIterator)]
+struct Numbers {
+    #[into_iterator(owned, ref,  ref_mut)]
+    numbers: Vec<i32>,
+    useless: bool,
+}
+```
+
+Code like this will be generated:
+
+```rust
+# struct Numbers {
+#     numbers: Vec<i32>,
+#     useless: bool,
+# }
+impl ::core::iter::IntoIterator for Numbers {
+    type Item = <Vec<i32> as ::core::iter::IntoIterator>::Item;
+    type IntoIter = <Vec<i32> as ::core::iter::IntoIterator>::IntoIter;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        <Vec<i32> as ::core::iter::IntoIterator>::into_iter(self.numbers)
+    }
+}
+
+impl<'__deriveMoreLifetime> ::core::iter::IntoIterator for &'__deriveMoreLifetime Numbers {
+    type Item = <&'__deriveMoreLifetime Vec<i32> as ::core::iter::IntoIterator>::Item;
+    type IntoIter = <&'__deriveMoreLifetime Vec<i32> as ::core::iter::IntoIterator>::IntoIter;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        <&'__deriveMoreLifetime Vec<i32> as ::core::iter::IntoIterator>::into_iter(&self.numbers)
+    }
+}
+
+impl<'__deriveMoreLifetime> ::core::iter::IntoIterator for &'__deriveMoreLifetime mut Numbers {
+    type Item = <&'__deriveMoreLifetime mut Vec<i32> as ::core::iter::IntoIterator>::Item;
+    type IntoIter = <&'__deriveMoreLifetime mut Vec<i32> as ::core::iter::IntoIterator>::IntoIter;
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        <&'__deriveMoreLifetime mut Vec<i32> as ::core::iter::IntoIterator>::into_iter(
+            &mut self.numbers,
+        )
+    }
+}
+```
+
+
+
+
+## Enums
+
+Deriving `IntoIterator` is not supported for enums.