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diff --git a/src/test/rustdoc/auxiliary/enum-primitive.rs b/src/test/rustdoc/auxiliary/enum-primitive.rs
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+// Copyright (c) 2015 Anders Kaseorg <andersk@mit.edu>
+
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the
+// “Software”), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to
+// permit persons to whom the Software is furnished to do so, subject to
+// the following conditions:
+
+// The above copyright notice and this permission notice shall be
+// included in all copies or substantial portions of the Software.
+
+// THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
+// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+// IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+// CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+// TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+// SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+//! This crate exports a macro `enum_from_primitive!` that wraps an
+//! `enum` declaration and automatically adds an implementation of
+//! `num::FromPrimitive` (reexported here), to allow conversion from
+//! primitive integers to the enum. It therefore provides an
+//! alternative to the built-in `#[derive(FromPrimitive)]`, which
+//! requires the unstable `std::num::FromPrimitive` and is disabled in
+//! Rust 1.0.
+//!
+//! # Example
+//!
+//! ```
+//! #[macro_use] extern crate enum_primitive;
+//! extern crate num_traits;
+//! use num_traits::FromPrimitive;
+//!
+//! enum_from_primitive! {
+//! #[derive(Debug, PartialEq)]
+//! enum FooBar {
+//!     Foo = 17,
+//!     Bar = 42,
+//!     Baz,
+//! }
+//! }
+//!
+//! fn main() {
+//!     assert_eq!(FooBar::from_i32(17), Some(FooBar::Foo));
+//!     assert_eq!(FooBar::from_i32(42), Some(FooBar::Bar));
+//!     assert_eq!(FooBar::from_i32(43), Some(FooBar::Baz));
+//!     assert_eq!(FooBar::from_i32(91), None);
+//! }
+//! ```
+
+pub mod num_traits {
+    pub trait FromPrimitive: Sized {
+        fn from_i64(n: i64) -> Option<Self>;
+        fn from_u64(n: u64) -> Option<Self>;
+    }
+}
+
+pub use std::option::Option;
+pub use num_traits::FromPrimitive;
+
+/// Helper macro for internal use by `enum_from_primitive!`.
+#[macro_export]
+macro_rules! enum_from_primitive_impl_ty {
+    ($meth:ident, $ty:ty, $name:ident, $( $variant:ident )*) => {
+        #[allow(non_upper_case_globals, unused)]
+        fn $meth(n: $ty) -> $crate::Option<Self> {
+            $( if n == $name::$variant as $ty {
+                $crate::Option::Some($name::$variant)
+            } else )* {
+                $crate::Option::None
+            }
+        }
+    };
+}
+
+/// Helper macro for internal use by `enum_from_primitive!`.
+#[macro_export]
+#[macro_use(enum_from_primitive_impl_ty)]
+macro_rules! enum_from_primitive_impl {
+    ($name:ident, $( $variant:ident )*) => {
+        impl $crate::FromPrimitive for $name {
+            enum_from_primitive_impl_ty! { from_i64, i64, $name, $( $variant )* }
+            enum_from_primitive_impl_ty! { from_u64, u64, $name, $( $variant )* }
+        }
+    };
+}
+
+/// Wrap this macro around an `enum` declaration to get an
+/// automatically generated implementation of `num::FromPrimitive`.
+#[macro_export]
+#[macro_use(enum_from_primitive_impl)]
+macro_rules! enum_from_primitive {
+    (
+        $( #[$enum_attr:meta] )*
+        enum $name:ident {
+            $( $( #[$variant_attr:meta] )* $variant:ident ),+
+            $( = $discriminator:expr, $( $( #[$variant_two_attr:meta] )* $variant_two:ident ),+ )*
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        enum $name {
+            $( $( #[$variant_attr] )* $variant ),+
+            $( = $discriminator, $( $( #[$variant_two_attr] )* $variant_two ),+ )*
+        }
+        enum_from_primitive_impl! { $name, $( $variant )+ $( $( $variant_two )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        enum $name:ident {
+            $( $( $( #[$variant_attr:meta] )* $variant:ident ),+ = $discriminator:expr ),*
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        enum $name {
+            $( $( $( #[$variant_attr] )* $variant ),+ = $discriminator ),*
+        }
+        enum_from_primitive_impl! { $name, $( $( $variant )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        enum $name:ident {
+            $( $( #[$variant_attr:meta] )* $variant:ident ),+
+            $( = $discriminator:expr, $( $( #[$variant_two_attr:meta] )* $variant_two:ident ),+ )*,
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        enum $name {
+            $( $( #[$variant_attr] )* $variant ),+
+            $( = $discriminator, $( $( #[$variant_two_attr] )* $variant_two ),+ )*,
+        }
+        enum_from_primitive_impl! { $name, $( $variant )+ $( $( $variant_two )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        enum $name:ident {
+            $( $( $( #[$variant_attr:meta] )* $variant:ident ),+ = $discriminator:expr ),+,
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        enum $name {
+            $( $( $( #[$variant_attr] )* $variant ),+ = $discriminator ),+,
+        }
+        enum_from_primitive_impl! { $name, $( $( $variant )+ )+ }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        pub enum $name:ident {
+            $( $( #[$variant_attr:meta] )* $variant:ident ),+
+            $( = $discriminator:expr, $( $( #[$variant_two_attr:meta] )* $variant_two:ident ),+ )*
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        pub enum $name {
+            $( $( #[$variant_attr] )* $variant ),+
+            $( = $discriminator, $( $( #[$variant_two_attr] )* $variant_two ),+ )*
+        }
+        enum_from_primitive_impl! { $name, $( $variant )+ $( $( $variant_two )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        pub enum $name:ident {
+            $( $( $( #[$variant_attr:meta] )* $variant:ident ),+ = $discriminator:expr ),*
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        pub enum $name {
+            $( $( $( #[$variant_attr] )* $variant ),+ = $discriminator ),*
+        }
+        enum_from_primitive_impl! { $name, $( $( $variant )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        pub enum $name:ident {
+            $( $( #[$variant_attr:meta] )* $variant:ident ),+
+            $( = $discriminator:expr, $( $( #[$variant_two_attr:meta] )* $variant_two:ident ),+ )*,
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        pub enum $name {
+            $( $( #[$variant_attr] )* $variant ),+
+            $( = $discriminator, $( $( #[$variant_two_attr] )* $variant_two ),+ )*,
+        }
+        enum_from_primitive_impl! { $name, $( $variant )+ $( $( $variant_two )+ )* }
+    };
+
+    (
+        $( #[$enum_attr:meta] )*
+        pub enum $name:ident {
+            $( $( $( #[$variant_attr:meta] )* $variant:ident ),+ = $discriminator:expr ),+,
+        }
+    ) => {
+        $( #[$enum_attr] )*
+        pub enum $name {
+            $( $( $( #[$variant_attr] )* $variant ),+ = $discriminator ),+,
+        }
+        enum_from_primitive_impl! { $name, $( $( $variant )+ )+ }
+    };
+}