rollup merge of #23538: aturon/conversion

Conflicts:
	src/librustc_back/rpath.rs

13 files changed, 314 insertions, 87 deletions

diff --git a/src/libstd/env.rs b/src/libstd/env.rs
index 24882c7f7ab..9d6933ce9c8 100644
--- a/src/libstd/env.rs
+++ b/src/libstd/env.rs
@@ -23,7 +23,7 @@ use error::Error;
 use ffi::{OsString, AsOsStr};
 use fmt;
 use io;
-use path::{AsPath, PathBuf};
+use path::{self, Path, PathBuf};
 use sync::atomic::{AtomicIsize, ATOMIC_ISIZE_INIT, Ordering};
 use sync::{StaticMutex, MUTEX_INIT};
 use sys::os as os_imp;
@@ -67,8 +67,8 @@ pub fn current_dir() -> io::Result<PathBuf> {
 /// println!("Successfully changed working directory to {}!", root.display());
 /// ```
 #[stable(feature = "env", since = "1.0.0")]
-pub fn set_current_dir<P: AsPath + ?Sized>(p: &P) -> io::Result<()> {
-    os_imp::chdir(p.as_path())
+pub fn set_current_dir<P: AsRef<Path> + ?Sized>(p: &P) -> io::Result<()> {
+    os_imp::chdir(p.as_ref())
 }
 
 static ENV_LOCK: StaticMutex = MUTEX_INIT;
diff --git a/src/libstd/ffi/c_str.rs b/src/libstd/ffi/c_str.rs
index fc4f03ff3a5..1760445a0fc 100644
--- a/src/libstd/ffi/c_str.rs
+++ b/src/libstd/ffi/c_str.rs
@@ -10,6 +10,7 @@
 
 #![unstable(feature = "std_misc")]
 
+use convert::Into;
 use cmp::{PartialEq, Eq, PartialOrd, Ord, Ordering};
 use error::{Error, FromError};
 use fmt;
@@ -130,6 +131,8 @@ pub struct NulError(usize, Vec<u8>);
 
 /// A conversion trait used by the constructor of `CString` for types that can
 /// be converted to a vector of bytes.
+#[deprecated(since = "1.0.0", reason = "use std::convert::Into<Vec<u8>> instead")]
+#[unstable(feature = "std_misc")]
 pub trait IntoBytes {
     /// Consumes this container, returning a vector of bytes.
     fn into_bytes(self) -> Vec<u8>;
@@ -163,8 +166,8 @@ impl CString {
     /// internal 0 byte. The error returned will contain the bytes as well as
     /// the position of the nul byte.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn new<T: IntoBytes>(t: T) -> Result<CString, NulError> {
-        let bytes = t.into_bytes();
+    pub fn new<T: Into<Vec<u8>>>(t: T) -> Result<CString, NulError> {
+        let bytes = t.into();
         match bytes.iter().position(|x| *x == 0) {
             Some(i) => Err(NulError(i, bytes)),
             None => Ok(unsafe { CString::from_vec_unchecked(bytes) }),
@@ -433,15 +436,19 @@ pub unsafe fn c_str_to_bytes_with_nul<'a>(raw: &'a *const libc::c_char)
     slice::from_raw_parts(*(raw as *const _ as *const *const u8), len as usize)
 }
 
+#[allow(deprecated)]
 impl<'a> IntoBytes for &'a str {
     fn into_bytes(self) -> Vec<u8> { self.as_bytes().to_vec() }
 }
+#[allow(deprecated)]
 impl<'a> IntoBytes for &'a [u8] {
     fn into_bytes(self) -> Vec<u8> { self.to_vec() }
 }
+#[allow(deprecated)]
 impl IntoBytes for String {
     fn into_bytes(self) -> Vec<u8> { self.into_bytes() }
 }
+#[allow(deprecated)]
 impl IntoBytes for Vec<u8> {
     fn into_bytes(self) -> Vec<u8> { self }
 }
diff --git a/src/libstd/ffi/os_str.rs b/src/libstd/ffi/os_str.rs
index feacbf1e98b..4d411046632 100644
--- a/src/libstd/ffi/os_str.rs
+++ b/src/libstd/ffi/os_str.rs
@@ -63,16 +63,18 @@ pub struct OsStr {
 impl OsString {
     /// Constructs an `OsString` at no cost by consuming a `String`.
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[deprecated(since = "1.0.0", reason = "use `from` instead")]
     pub fn from_string(s: String) -> OsString {
-        OsString { inner: Buf::from_string(s) }
+        OsString::from(s)
     }
 
     /// Constructs an `OsString` by copying from a `&str` slice.
     ///
     /// Equivalent to: `OsString::from_string(String::from_str(s))`.
     #[stable(feature = "rust1", since = "1.0.0")]
+    #[deprecated(since = "1.0.0", reason = "use `from` instead")]
     pub fn from_str(s: &str) -> OsString {
-        OsString { inner: Buf::from_str(s) }
+        OsString::from(s)
     }
 
     /// Constructs a new empty `OsString`.
@@ -98,8 +100,36 @@ impl OsString {
 
     /// Extend the string with the given `&OsStr` slice.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn push<T: AsOsStr + ?Sized>(&mut self, s: &T) {
-        self.inner.push_slice(&s.as_os_str().inner)
+    pub fn push<T: AsRef<OsStr>>(&mut self, s: T) {
+        self.inner.push_slice(&s.as_ref().inner)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl From<String> for OsString {
+    fn from(s: String) -> OsString {
+        OsString { inner: Buf::from_string(s) }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a String> for OsString {
+    fn from(s: &'a String) -> OsString {
+        OsString { inner: Buf::from_str(s) }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a str> for OsString {
+    fn from(s: &'a str) -> OsString {
+        OsString { inner: Buf::from_str(s) }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a OsStr> for OsString {
+    fn from(s: &'a OsStr) -> OsString {
+        OsString { inner: s.inner.to_owned() }
     }
 }
 
@@ -316,37 +346,76 @@ impl ToOwned for OsStr {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl<'a, T: AsOsStr + ?Sized> AsOsStr for &'a T {
     fn as_os_str(&self) -> &OsStr {
         (*self).as_os_str()
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for OsStr {
     fn as_os_str(&self) -> &OsStr {
         self
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for OsString {
     fn as_os_str(&self) -> &OsStr {
         &self[..]
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for str {
     fn as_os_str(&self) -> &OsStr {
         OsStr::from_str(self)
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for String {
     fn as_os_str(&self) -> &OsStr {
         OsStr::from_str(&self[..])
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for OsStr {
+    fn as_ref(&self) -> &OsStr {
+        self
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for OsString {
+    fn as_ref(&self) -> &OsStr {
+        self
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for str {
+    fn as_ref(&self) -> &OsStr {
+        OsStr::from_str(self)
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for String {
+    fn as_ref(&self) -> &OsStr {
+        OsStr::from_str(&self[..])
+    }
+}
+
 #[allow(deprecated)]
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for Path {
     #[cfg(unix)]
     fn as_os_str(&self) -> &OsStr {
diff --git a/src/libstd/fs/mod.rs b/src/libstd/fs/mod.rs
index 7df6d6887a2..ab65004f5d1 100644
--- a/src/libstd/fs/mod.rs
+++ b/src/libstd/fs/mod.rs
@@ -20,7 +20,7 @@
 use core::prelude::*;
 
 use io::{self, Error, ErrorKind, SeekFrom, Seek, Read, Write};
-use path::{AsPath, Path, PathBuf};
+use path::{Path, PathBuf};
 use sys::fs2 as fs_imp;
 use sys_common::{AsInnerMut, FromInner, AsInner};
 use vec::Vec;
@@ -129,7 +129,7 @@ impl File {
     /// This function will return an error if `path` does not already exist.
     /// Other errors may also be returned according to `OpenOptions::open`.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn open<P: AsPath>(path: P) -> io::Result<File> {
+    pub fn open<P: AsRef<Path>>(path: P) -> io::Result<File> {
         OpenOptions::new().read(true).open(path)
     }
 
@@ -140,7 +140,7 @@ impl File {
     ///
     /// See the `OpenOptions::open` function for more details.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn create<P: AsPath>(path: P) -> io::Result<File> {
+    pub fn create<P: AsRef<Path>>(path: P) -> io::Result<File> {
         OpenOptions::new().write(true).create(true).truncate(true).open(path)
     }
 
@@ -302,8 +302,8 @@ impl OpenOptions {
     ///   permissions for
     /// * Filesystem-level errors (full disk, etc)
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn open<P: AsPath>(&self, path: P) -> io::Result<File> {
-        let path = path.as_path();
+    pub fn open<P: AsRef<Path>>(&self, path: P) -> io::Result<File> {
+        let path = path.as_ref();
         let inner = try!(fs_imp::File::open(path, &self.0));
         Ok(File { path: path.to_path_buf(), inner: inner })
     }
@@ -415,8 +415,8 @@ impl DirEntry {
 /// user lacks permissions to remove the file, or if some other filesystem-level
 /// error occurs.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn remove_file<P: AsPath>(path: P) -> io::Result<()> {
-    fs_imp::unlink(path.as_path())
+pub fn remove_file<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    fs_imp::unlink(path.as_ref())
 }
 
 /// Given a path, query the file system to get information about a file,
@@ -443,8 +443,8 @@ pub fn remove_file<P: AsPath>(path: P) -> io::Result<()> {
 /// permissions to perform a `metadata` call on the given `path` or if there
 /// is no entry in the filesystem at the provided path.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn metadata<P: AsPath>(path: P) -> io::Result<Metadata> {
-    fs_imp::stat(path.as_path()).map(Metadata)
+pub fn metadata<P: AsRef<Path>>(path: P) -> io::Result<Metadata> {
+    fs_imp::stat(path.as_ref()).map(Metadata)
 }
 
 /// Rename a file or directory to a new name.
@@ -464,8 +464,8 @@ pub fn metadata<P: AsPath>(path: P) -> io::Result<Metadata> {
 /// reside on separate filesystems, or if some other intermittent I/O error
 /// occurs.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn rename<P: AsPath, Q: AsPath>(from: P, to: Q) -> io::Result<()> {
-    fs_imp::rename(from.as_path(), to.as_path())
+pub fn rename<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<()> {
+    fs_imp::rename(from.as_ref(), to.as_ref())
 }
 
 /// Copies the contents of one file to another. This function will also
@@ -494,9 +494,9 @@ pub fn rename<P: AsPath, Q: AsPath>(from: P, to: Q) -> io::Result<()> {
 /// * The current process does not have the permission rights to access
 ///   `from` or write `to`
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn copy<P: AsPath, Q: AsPath>(from: P, to: Q) -> io::Result<u64> {
-    let from = from.as_path();
-    let to = to.as_path();
+pub fn copy<P: AsRef<Path>, Q: AsRef<Path>>(from: P, to: Q) -> io::Result<u64> {
+    let from = from.as_ref();
+    let to = to.as_ref();
     if !from.is_file() {
         return Err(Error::new(ErrorKind::InvalidInput,
                               "the source path is not an existing file",
@@ -517,16 +517,16 @@ pub fn copy<P: AsPath, Q: AsPath>(from: P, to: Q) -> io::Result<u64> {
 /// The `dst` path will be a link pointing to the `src` path. Note that systems
 /// often require these two paths to both be located on the same filesystem.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn hard_link<P: AsPath, Q: AsPath>(src: P, dst: Q) -> io::Result<()> {
-    fs_imp::link(src.as_path(), dst.as_path())
+pub fn hard_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
+    fs_imp::link(src.as_ref(), dst.as_ref())
 }
 
 /// Creates a new soft link on the filesystem.
 ///
 /// The `dst` path will be a soft link pointing to the `src` path.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn soft_link<P: AsPath, Q: AsPath>(src: P, dst: Q) -> io::Result<()> {
-    fs_imp::symlink(src.as_path(), dst.as_path())
+pub fn soft_link<P: AsRef<Path>, Q: AsRef<Path>>(src: P, dst: Q) -> io::Result<()> {
+    fs_imp::symlink(src.as_ref(), dst.as_ref())
 }
 
 /// Reads a soft link, returning the file that the link points to.
@@ -537,8 +537,8 @@ pub fn soft_link<P: AsPath, Q: AsPath>(src: P, dst: Q) -> io::Result<()> {
 /// reading a file that does not exist or reading a file that is not a soft
 /// link.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn read_link<P: AsPath>(path: P) -> io::Result<PathBuf> {
-    fs_imp::readlink(path.as_path())
+pub fn read_link<P: AsRef<Path>>(path: P) -> io::Result<PathBuf> {
+    fs_imp::readlink(path.as_ref())
 }
 
 /// Create a new, empty directory at the provided path
@@ -556,8 +556,8 @@ pub fn read_link<P: AsPath>(path: P) -> io::Result<PathBuf> {
 /// This function will return an error if the user lacks permissions to make a
 /// new directory at the provided `path`, or if the directory already exists.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn create_dir<P: AsPath>(path: P) -> io::Result<()> {
-    fs_imp::mkdir(path.as_path())
+pub fn create_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    fs_imp::mkdir(path.as_ref())
 }
 
 /// Recursively create a directory and all of its parent components if they
@@ -570,8 +570,8 @@ pub fn create_dir<P: AsPath>(path: P) -> io::Result<()> {
 /// error conditions for when a directory is being created (after it is
 /// determined to not exist) are outlined by `fs::create_dir`.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn create_dir_all<P: AsPath>(path: P) -> io::Result<()> {
-    let path = path.as_path();
+pub fn create_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    let path = path.as_ref();
     if path.is_dir() { return Ok(()) }
     if let Some(p) = path.parent() { try!(create_dir_all(p)) }
     create_dir(path)
@@ -592,8 +592,8 @@ pub fn create_dir_all<P: AsPath>(path: P) -> io::Result<()> {
 /// This function will return an error if the user lacks permissions to remove
 /// the directory at the provided `path`, or if the directory isn't empty.
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn remove_dir<P: AsPath>(path: P) -> io::Result<()> {
-    fs_imp::rmdir(path.as_path())
+pub fn remove_dir<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    fs_imp::rmdir(path.as_ref())
 }
 
 /// Removes a directory at this path, after removing all its contents. Use
@@ -606,8 +606,8 @@ pub fn remove_dir<P: AsPath>(path: P) -> io::Result<()> {
 ///
 /// See `file::remove_file` and `fs::remove_dir`
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn remove_dir_all<P: AsPath>(path: P) -> io::Result<()> {
-    let path = path.as_path();
+pub fn remove_dir_all<P: AsRef<Path>>(path: P) -> io::Result<()> {
+    let path = path.as_ref();
     for child in try!(read_dir(path)) {
         let child = try!(child).path();
         let stat = try!(lstat(&*child));
@@ -659,8 +659,8 @@ pub fn remove_dir_all<P: AsPath>(path: P) -> io::Result<()> {
 /// the process lacks permissions to view the contents or if the `path` points
 /// at a non-directory file
 #[stable(feature = "rust1", since = "1.0.0")]
-pub fn read_dir<P: AsPath>(path: P) -> io::Result<ReadDir> {
-    fs_imp::readdir(path.as_path()).map(ReadDir)
+pub fn read_dir<P: AsRef<Path>>(path: P) -> io::Result<ReadDir> {
+    fs_imp::readdir(path.as_ref()).map(ReadDir)
 }
 
 /// Returns an iterator that will recursively walk the directory structure
@@ -675,7 +675,7 @@ pub fn read_dir<P: AsPath>(path: P) -> io::Result<ReadDir> {
            reason = "the precise semantics and defaults for a recursive walk \
                      may change and this may end up accounting for files such \
                      as symlinks differently")]
-pub fn walk_dir<P: AsPath>(path: P) -> io::Result<WalkDir> {
+pub fn walk_dir<P: AsRef<Path>>(path: P) -> io::Result<WalkDir> {
     let start = try!(read_dir(path));
     Ok(WalkDir { cur: Some(start), stack: Vec::new() })
 }
@@ -761,9 +761,9 @@ impl PathExt for Path {
            reason = "the argument type of u64 is not quite appropriate for \
                      this function and may change if the standard library \
                      gains a type to represent a moment in time")]
-pub fn set_file_times<P: AsPath>(path: P, accessed: u64,
+pub fn set_file_times<P: AsRef<Path>>(path: P, accessed: u64,
                                  modified: u64) -> io::Result<()> {
-    fs_imp::utimes(path.as_path(), accessed, modified)
+    fs_imp::utimes(path.as_ref(), accessed, modified)
 }
 
 /// Changes the permissions found on a file or a directory.
@@ -790,8 +790,8 @@ pub fn set_file_times<P: AsPath>(path: P, accessed: u64,
            reason = "a more granual ability to set specific permissions may \
                      be exposed on the Permissions structure itself and this \
                      method may not always exist")]
-pub fn set_permissions<P: AsPath>(path: P, perm: Permissions) -> io::Result<()> {
-    fs_imp::set_perm(path.as_path(), perm.0)
+pub fn set_permissions<P: AsRef<Path>>(path: P, perm: Permissions) -> io::Result<()> {
+    fs_imp::set_perm(path.as_ref(), perm.0)
 }
 
 #[cfg(test)]
diff --git a/src/libstd/fs/tempdir.rs b/src/libstd/fs/tempdir.rs
index 8f32d7a5864..a9717e36323 100644
--- a/src/libstd/fs/tempdir.rs
+++ b/src/libstd/fs/tempdir.rs
@@ -18,7 +18,7 @@ use prelude::v1::*;
 use env;
 use io::{self, Error, ErrorKind};
 use fs;
-use path::{self, PathBuf, AsPath};
+use path::{self, PathBuf};
 use rand::{thread_rng, Rng};
 
 /// A wrapper for a path to temporary directory implementing automatic
@@ -43,10 +43,9 @@ impl TempDir {
     ///
     /// If no directory can be created, `Err` is returned.
     #[allow(deprecated)] // rand usage
-    pub fn new_in<P: AsPath + ?Sized>(tmpdir: &P, prefix: &str)
-                                      -> io::Result<TempDir> {
+    pub fn new_in<P: AsRef<path::Path>>(tmpdir: P, prefix: &str) -> io::Result<TempDir> {
         let storage;
-        let mut tmpdir = tmpdir.as_path();
+        let mut tmpdir = tmpdir.as_ref();
         if !tmpdir.is_absolute() {
             let cur_dir = try!(env::current_dir());
             storage = cur_dir.join(tmpdir);
diff --git a/src/libstd/lib.rs b/src/libstd/lib.rs
index b055796ba54..1488c7969f6 100644
--- a/src/libstd/lib.rs
+++ b/src/libstd/lib.rs
@@ -126,8 +126,10 @@
 #![feature(hash)]
 #![feature(int_uint)]
 #![feature(unique)]
+#![feature(convert)]
 #![feature(allow_internal_unstable)]
 #![feature(str_char)]
+#![feature(into_cow)]
 #![cfg_attr(test, feature(test, rustc_private))]
 
 // Don't link to std. We are std.
@@ -169,6 +171,7 @@ pub use core::any;
 pub use core::cell;
 pub use core::clone;
 #[cfg(not(test))] pub use core::cmp;
+pub use core::convert;
 pub use core::default;
 #[allow(deprecated)]
 pub use core::finally;
diff --git a/src/libstd/net/ip.rs b/src/libstd/net/ip.rs
index 73c2464a6b2..d737ad17ff8 100644
--- a/src/libstd/net/ip.rs
+++ b/src/libstd/net/ip.rs
@@ -374,7 +374,6 @@ impl fmt::Display for Ipv6Addr {
                             .iter()
                             .map(|&seg| format!("{:x}", seg))
                             .collect::<Vec<String>>()
-                            .as_slice()
                             .connect(":")
                     }
 
diff --git a/src/libstd/os.rs b/src/libstd/os.rs
index 3870b8614ff..72f9338b456 100644
--- a/src/libstd/os.rs
+++ b/src/libstd/os.rs
@@ -38,6 +38,7 @@ use self::MapError::*;
 
 use boxed::Box;
 use clone::Clone;
+use convert::From;
 use env;
 use error::{FromError, Error};
 use ffi::{OsString, OsStr};
@@ -79,12 +80,12 @@ fn err2old(new: ::io::Error) -> IoError {
 
 #[cfg(windows)]
 fn path2new(path: &Path) -> PathBuf {
-    PathBuf::new(path.as_str().unwrap())
+    PathBuf::from(path.as_str().unwrap())
 }
 #[cfg(unix)]
 fn path2new(path: &Path) -> PathBuf {
     use os::unix::prelude::*;
-    PathBuf::new(<OsStr as OsStrExt>::from_bytes(path.as_vec()))
+    PathBuf::from(<OsStr as OsStrExt>::from_bytes(path.as_vec()))
 }
 
 #[cfg(unix)]
diff --git a/src/libstd/path.rs b/src/libstd/path.rs
index 05c7761be7b..8ee33e94fe7 100644
--- a/src/libstd/path.rs
+++ b/src/libstd/path.rs
@@ -106,6 +106,7 @@ use cmp;
 use iter::{self, IntoIterator};
 use mem;
 use ops::{self, Deref};
+use string::String;
 use vec::Vec;
 use fmt;
 
@@ -527,6 +528,13 @@ impl<'a> Component<'a> {
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> AsRef<OsStr> for Component<'a> {
+    fn as_ref(&self) -> &OsStr {
+        self.as_os_str()
+    }
+}
+
 /// The core iterator giving the components of a path.
 ///
 /// See the module documentation for an in-depth explanation of components and
@@ -601,6 +609,7 @@ impl<'a> Components<'a> {
     }
 
     /// Extract a slice corresponding to the portion of the path remaining for iteration.
+    #[stable(feature = "rust1", since = "1.0.0")]
     pub fn as_path(&self) -> &'a Path {
         let mut comps = self.clone();
         if comps.front == State::Body { comps.trim_left(); }
@@ -695,6 +704,20 @@ impl<'a> Components<'a> {
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> AsRef<Path> for Components<'a> {
+    fn as_ref(&self) -> &Path {
+        self.as_path()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> AsRef<OsStr> for Components<'a> {
+    fn as_ref(&self) -> &OsStr {
+        self.as_path().as_os_str()
+    }
+}
+
 impl<'a> Iter<'a> {
     /// Extract a slice corresponding to the portion of the path remaining for iteration.
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -704,6 +727,20 @@ impl<'a> Iter<'a> {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> AsRef<Path> for Iter<'a> {
+    fn as_ref(&self) -> &Path {
+        self.as_path()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> AsRef<OsStr> for Iter<'a> {
+    fn as_ref(&self) -> &OsStr {
+        self.as_path().as_os_str()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
 impl<'a> Iterator for Iter<'a> {
     type Item = &'a OsStr;
 
@@ -873,11 +910,10 @@ impl PathBuf {
         unsafe { mem::transmute(self) }
     }
 
-    /// Allocate a `PathBuf` with initial contents given by the
-    /// argument.
+    /// Allocate an empty `PathBuf`.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn new<S: AsOsStr>(s: S) -> PathBuf {
-        PathBuf { inner: s.as_os_str().to_os_string() }
+    pub fn new() -> PathBuf {
+        PathBuf { inner: OsString::new() }
     }
 
     /// Extend `self` with `path`.
@@ -890,8 +926,8 @@ impl PathBuf {
     ///   replaces everything except for the prefix (if any) of `self`.
     /// * if `path` has a prefix but no root, it replaces `self.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn push<P: AsPath>(&mut self, path: P) {
-        let path = path.as_path();
+    pub fn push<P: AsRef<Path>>(&mut self, path: P) {
+        let path = path.as_ref();
 
         // in general, a separator is needed if the rightmost byte is not a separator
         let mut need_sep = self.as_mut_vec().last().map(|c| !is_sep_byte(*c)).unwrap_or(false);
@@ -958,12 +994,12 @@ impl PathBuf {
     /// assert!(buf == PathBuf::new("/baz.txt"));
     /// ```
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn set_file_name<S: AsOsStr>(&mut self, file_name: S) {
+    pub fn set_file_name<S: AsRef<OsStr>>(&mut self, file_name: S) {
         if self.file_name().is_some() {
             let popped = self.pop();
             debug_assert!(popped);
         }
-        self.push(file_name.as_os_str());
+        self.push(file_name.as_ref());
     }
 
     /// Updates `self.extension()` to `extension`.
@@ -973,15 +1009,15 @@ impl PathBuf {
     /// Otherwise, returns `true`; if `self.extension()` is `None`, the extension
     /// is added; otherwise it is replaced.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn set_extension<S: AsOsStr>(&mut self, extension: S) -> bool {
+    pub fn set_extension<S: AsRef<OsStr>>(&mut self, extension: S) -> bool {
         if self.file_name().is_none() { return false; }
 
         let mut stem = match self.file_stem() {
             Some(stem) => stem.to_os_string(),
-            None => OsString::from_str(""),
+            None => OsString::new(),
         };
 
-        let extension = extension.as_os_str();
+        let extension = extension.as_ref();
         if os_str_as_u8_slice(extension).len() > 0 {
             stem.push(".");
             stem.push(extension);
@@ -999,16 +1035,65 @@ impl PathBuf {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<P: AsPath> iter::FromIterator<P> for PathBuf {
+impl<'a> From<&'a Path> for PathBuf {
+    fn from(s: &'a Path) -> PathBuf {
+        s.to_path_buf()
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a str> for PathBuf {
+    fn from(s: &'a str) -> PathBuf {
+        PathBuf::from(OsString::from(s))
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a String> for PathBuf {
+    fn from(s: &'a String) -> PathBuf {
+        PathBuf::from(OsString::from(s))
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl From<String> for PathBuf {
+    fn from(s: String) -> PathBuf {
+        PathBuf::from(OsString::from(s))
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a OsStr> for PathBuf {
+    fn from(s: &'a OsStr) -> PathBuf {
+        PathBuf::from(OsString::from(s))
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a> From<&'a OsString> for PathBuf {
+    fn from(s: &'a OsString) -> PathBuf {
+        PathBuf::from(s.to_os_string())
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl From<OsString> for PathBuf {
+    fn from(s: OsString) -> PathBuf {
+        PathBuf { inner: s }
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<P: AsRef<Path>> iter::FromIterator<P> for PathBuf {
     fn from_iter<I: IntoIterator<Item = P>>(iter: I) -> PathBuf {
-        let mut buf = PathBuf::new("");
+        let mut buf = PathBuf::new();
         buf.extend(iter);
         buf
     }
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<P: AsPath> iter::Extend<P> for PathBuf {
+impl<P: AsRef<Path>> iter::Extend<P> for PathBuf {
     fn extend<I: IntoIterator<Item = P>>(&mut self, iter: I) {
         for p in iter {
             self.push(p)
@@ -1084,12 +1169,27 @@ impl cmp::Ord for PathBuf {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for PathBuf {
+    fn as_ref(&self) -> &OsStr {
+        &self.inner[..]
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for PathBuf {
     fn as_os_str(&self) -> &OsStr {
         &self.inner[..]
     }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl Into<OsString> for PathBuf {
+    fn into(self) -> OsString {
+        self.inner
+    }
+}
+
 /// A slice of a path (akin to `str`).
 ///
 /// This type supports a number of operations for inspecting a path, including
@@ -1133,8 +1233,14 @@ impl Path {
     ///
     /// This is a cost-free conversion.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn new<S: ?Sized + AsOsStr>(s: &S) -> &Path {
-        unsafe { mem::transmute(s.as_os_str()) }
+    pub fn new<S: AsRef<OsStr> + ?Sized>(s: &S) -> &Path {
+        unsafe { mem::transmute(s.as_ref()) }
+    }
+
+    /// Yield the underlying `OsStr` slice.
+    #[stable(feature = "rust1", since = "1.0.0")]
+    pub fn as_os_str(&self) -> &OsStr {
+        &self.inner
     }
 
     /// Yield a `&str` slice if the `Path` is valid unicode.
@@ -1156,7 +1262,7 @@ impl Path {
     /// Convert a `Path` to an owned `PathBuf`.
     #[stable(feature = "rust1", since = "1.0.0")]
     pub fn to_path_buf(&self) -> PathBuf {
-        PathBuf::new(self)
+        PathBuf::from(self.inner.to_os_string())
     }
 
     /// A path is *absolute* if it is independent of the current directory.
@@ -1247,22 +1353,21 @@ impl Path {
     /// If `base` is not a prefix of `self` (i.e. `starts_with`
     /// returns false), then `relative_from` returns `None`.
     #[unstable(feature = "path_relative_from", reason = "see #23284")]
-    pub fn relative_from<'a, P: ?Sized>(&'a self, base: &'a P) -> Option<&Path> where
-        P: AsPath
+    pub fn relative_from<'a, P: ?Sized + AsRef<Path>>(&'a self, base: &'a P) -> Option<&Path>
     {
-        iter_after(self.components(), base.as_path().components()).map(|c| c.as_path())
+        iter_after(self.components(), base.as_ref().components()).map(|c| c.as_path())
     }
 
     /// Determines whether `base` is a prefix of `self`.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn starts_with<P: AsPath>(&self, base: P) -> bool {
-        iter_after(self.components(), base.as_path().components()).is_some()
+    pub fn starts_with<P: AsRef<Path>>(&self, base: P) -> bool {
+        iter_after(self.components(), base.as_ref().components()).is_some()
     }
 
     /// Determines whether `child` is a suffix of `self`.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn ends_with<P: AsPath>(&self, child: P) -> bool {
-        iter_after(self.components().rev(), child.as_path().components().rev()).is_some()
+    pub fn ends_with<P: AsRef<Path>>(&self, child: P) -> bool {
+        iter_after(self.components().rev(), child.as_ref().components().rev()).is_some()
     }
 
     /// Extract the stem (non-extension) portion of `self.file()`.
@@ -1295,7 +1400,7 @@ impl Path {
     ///
     /// See `PathBuf::push` for more details on what it means to adjoin a path.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn join<P: AsPath>(&self, path: P) -> PathBuf {
+    pub fn join<P: AsRef<Path>>(&self, path: P) -> PathBuf {
         let mut buf = self.to_path_buf();
         buf.push(path);
         buf
@@ -1305,7 +1410,7 @@ impl Path {
     ///
     /// See `PathBuf::set_file_name` for more details.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn with_file_name<S: AsOsStr>(&self, file_name: S) -> PathBuf {
+    pub fn with_file_name<S: AsRef<OsStr>>(&self, file_name: S) -> PathBuf {
         let mut buf = self.to_path_buf();
         buf.set_file_name(file_name);
         buf
@@ -1315,7 +1420,7 @@ impl Path {
     ///
     /// See `PathBuf::set_extension` for more details.
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn with_extension<S: AsOsStr>(&self, extension: S) -> PathBuf {
+    pub fn with_extension<S: AsRef<OsStr>>(&self, extension: S) -> PathBuf {
         let mut buf = self.to_path_buf();
         buf.set_extension(extension);
         buf
@@ -1349,6 +1454,14 @@ impl Path {
 }
 
 #[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<OsStr> for Path {
+    fn as_ref(&self) -> &OsStr {
+        &self.inner
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+#[deprecated(since = "1.0.0", reason = "trait is deprecated")]
 impl AsOsStr for Path {
     fn as_os_str(&self) -> &OsStr {
         &self.inner
@@ -1408,6 +1521,7 @@ impl cmp::Ord for Path {
 
 /// Freely convertible to a `Path`.
 #[unstable(feature = "std_misc")]
+#[deprecated(since = "1.0.0", reason = "use std::convert::AsRef<Path> instead")]
 pub trait AsPath {
     /// Convert to a `Path`.
     #[unstable(feature = "std_misc")]
@@ -1415,10 +1529,42 @@ pub trait AsPath {
 }
 
 #[unstable(feature = "std_misc")]
+#[deprecated(since = "1.0.0", reason = "use std::convert::AsRef<Path> instead")]
+#[allow(deprecated)]
 impl<T: AsOsStr + ?Sized> AsPath for T {
     fn as_path(&self) -> &Path { Path::new(self.as_os_str()) }
 }
 
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for Path {
+    fn as_ref(&self) -> &Path { self }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for OsStr {
+    fn as_ref(&self) -> &Path { Path::new(self) }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for OsString {
+    fn as_ref(&self) -> &Path { Path::new(self) }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for str {
+    fn as_ref(&self) -> &Path { Path::new(self) }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for String {
+    fn as_ref(&self) -> &Path { Path::new(self) }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl AsRef<Path> for PathBuf {
+    fn as_ref(&self) -> &Path { self }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
diff --git a/src/libstd/prelude/v1.rs b/src/libstd/prelude/v1.rs
index a0b4c80e9f3..6e12ac1a226 100644
--- a/src/libstd/prelude/v1.rs
+++ b/src/libstd/prelude/v1.rs
@@ -29,6 +29,8 @@
 #[doc(no_inline)] pub use clone::Clone;
 #[stable(feature = "rust1", since = "1.0.0")]
 #[doc(no_inline)] pub use cmp::{PartialEq, PartialOrd, Eq, Ord};
+#[unstable(feature = "convert")]
+#[doc(no_inline)] pub use convert::{AsRef, AsMut, Into, From};
 #[stable(feature = "rust1", since = "1.0.0")]
 #[doc(no_inline)] pub use iter::DoubleEndedIterator;
 #[stable(feature = "rust1", since = "1.0.0")]
@@ -40,8 +42,10 @@
 #[stable(feature = "rust1", since = "1.0.0")]
 #[doc(no_inline)] pub use result::Result::{self, Ok, Err};
 #[stable(feature = "rust1", since = "1.0.0")]
+#[allow(deprecated)]
 #[doc(no_inline)] pub use slice::{SliceConcatExt, AsSlice};
 #[stable(feature = "rust1", since = "1.0.0")]
+#[allow(deprecated)]
 #[doc(no_inline)] pub use str::Str;
 #[stable(feature = "rust1", since = "1.0.0")]
 #[doc(no_inline)] pub use string::{String, ToString};
diff --git a/src/libstd/process.rs b/src/libstd/process.rs
index 6b09636c1df..d11c3d22144 100644
--- a/src/libstd/process.rs
+++ b/src/libstd/process.rs
@@ -19,8 +19,8 @@ use io::prelude::*;
 use ffi::AsOsStr;
 use fmt;
 use io::{self, Error, ErrorKind};
-use path::AsPath;
 use libc;
+use path;
 use sync::mpsc::{channel, Receiver};
 use sys::pipe2::{self, AnonPipe};
 use sys::process2::Process as ProcessImp;
@@ -198,8 +198,8 @@ impl Command {
 
     /// Set the working directory for the child process.
     #[stable(feature = "process", since = "1.0.0")]
-    pub fn current_dir<P: AsPath>(&mut self, dir: P) -> &mut Command {
-        self.inner.cwd(dir.as_path().as_os_str());
+    pub fn current_dir<P: AsRef<path::Path>>(&mut self, dir: P) -> &mut Command {
+        self.inner.cwd(dir.as_ref().as_os_str());
         self
     }
 
diff --git a/src/libstd/sys/unix/fs2.rs b/src/libstd/sys/unix/fs2.rs
index ea74aab3331..202e5ddaec4 100644
--- a/src/libstd/sys/unix/fs2.rs
+++ b/src/libstd/sys/unix/fs2.rs
@@ -338,8 +338,7 @@ pub fn readlink(p: &Path) -> io::Result<PathBuf> {
         }));
         buf.set_len(n as usize);
     }
-    let s: OsString = OsStringExt::from_vec(buf);
-    Ok(PathBuf::new(&s))
+    Ok(PathBuf::from(OsString::from_vec(buf)))
 }
 
 pub fn symlink(src: &Path, dst: &Path) -> io::Result<()> {
diff --git a/src/libstd/sys/unix/os.rs b/src/libstd/sys/unix/os.rs
index a5a2f71acb7..6c191689255 100644
--- a/src/libstd/sys/unix/os.rs
+++ b/src/libstd/sys/unix/os.rs
@@ -36,7 +36,7 @@ const BUF_BYTES: usize = 2048;
 const TMPBUF_SZ: usize = 128;
 
 fn bytes2path(b: &[u8]) -> PathBuf {
-    PathBuf::new(<OsStr as OsStrExt>::from_bytes(b))
+    PathBuf::from(<OsStr as OsStrExt>::from_bytes(b))
 }
 
 fn os2path(os: OsString) -> PathBuf {
@@ -253,7 +253,7 @@ pub fn current_exe() -> io::Result<PathBuf> {
         let err = _NSGetExecutablePath(v.as_mut_ptr() as *mut i8, &mut sz);
         if err != 0 { return Err(io::Error::last_os_error()); }
         v.set_len(sz as uint - 1); // chop off trailing NUL
-        Ok(PathBuf::new(OsString::from_vec(v)))
+        Ok(PathBuf::from(OsString::from_vec(v)))
     }
 }
 
@@ -466,9 +466,9 @@ pub fn page_size() -> usize {
 pub fn temp_dir() -> PathBuf {
     getenv("TMPDIR".as_os_str()).map(os2path).unwrap_or_else(|| {
         if cfg!(target_os = "android") {
-            PathBuf::new("/data/local/tmp")
+            PathBuf::from("/data/local/tmp")
         } else {
-            PathBuf::new("/tmp")
+            PathBuf::from("/tmp")
         }
     })
 }