Refactor `UserTypeAnnotation`.

[rust.git] / src / libserialize / serialize.rs

diff --git a/src/libserialize/serialize.rs b/src/libserialize/serialize.rs
index f0b49c3d9bc8faec0db174a40eeafe0f555e8d70..03844b387ac81e0f8f01fda2682b1ffaf8ef7ade 100644 (file)
--- a/src/libserialize/serialize.rs
+++ b/src/libserialize/serialize.rs
@@ -1,13 +1,3 @@
-// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
 //! Support code for encoding and decoding types.
 
 /*
@@ -16,6 +6,7 @@
 
 use std::borrow::Cow;
 use std::intrinsics;
+use std::marker::PhantomData;
 use std::path;
 use std::rc::Rc;
 use std::cell::{Cell, RefCell};
@@ -547,6 +538,19 @@ fn decode<D: Decoder>(d: &mut D) -> Result<(), D::Error> {
     }
 }
 
+impl<T> Encodable for PhantomData<T> {
+    fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
+        s.emit_unit()
+    }
+}
+
+impl<T> Decodable for PhantomData<T> {
+    fn decode<D: Decoder>(d: &mut D) -> Result<PhantomData<T>, D::Error> {
+        d.read_nil()?;
+        Ok(PhantomData)
+    }
+}
+
 impl<'a, T: ?Sized + Encodable> Encodable for &'a T {
     fn encode<S: Encoder>(&self, s: &mut S) -> Result<(), S::Error> {
         (**self).encode(s)