Auto merge of #21680 - japaric:slice, r=alexcrichton

Replaces `slice_*` method calls with slicing syntax, and removes `as_slice()` calls that are redundant due to `Deref`.

3 files changed, 5 insertions, 5 deletions

diff --git a/src/libstd/old_io/fs.rs b/src/libstd/old_io/fs.rs
index a1ac5d2eab0..5a4ce24be0d 100644
--- a/src/libstd/old_io/fs.rs
+++ b/src/libstd/old_io/fs.rs
@@ -936,11 +936,11 @@ mod test {
         {
             let mut read_stream = File::open_mode(filename, Open, Read);
             {
-                let read_buf = read_mem.slice_mut(0, 4);
+                let read_buf = &mut read_mem[0..4];
                 check!(read_stream.read(read_buf));
             }
             {
-                let read_buf = read_mem.slice_mut(4, 8);
+                let read_buf = &mut read_mem[4..8];
                 check!(read_stream.read(read_buf));
             }
         }
@@ -971,7 +971,7 @@ mod test {
         }
         check!(unlink(filename));
         let read_str = str::from_utf8(&read_mem).unwrap();
-        assert_eq!(read_str, message.slice(4, 8));
+        assert_eq!(read_str, &message[4..8]);
         assert_eq!(tell_pos_pre_read, set_cursor);
         assert_eq!(tell_pos_post_read, message.len() as u64);
     }
diff --git a/src/libstd/old_io/mem.rs b/src/libstd/old_io/mem.rs
index 254daf3202a..750bc50288a 100644
--- a/src/libstd/old_io/mem.rs
+++ b/src/libstd/old_io/mem.rs
@@ -647,7 +647,7 @@ mod test {
         assert!(r.read_at_least(buf.len(), &mut buf).is_ok());
         let b: &[_] = &[1, 2, 3];
         assert_eq!(buf, b);
-        assert!(r.read_at_least(0, buf.slice_to_mut(0)).is_ok());
+        assert!(r.read_at_least(0, &mut buf[..0]).is_ok());
         assert_eq!(buf, b);
         assert!(r.read_at_least(buf.len(), &mut buf).is_ok());
         let b: &[_] = &[4, 5, 6];
diff --git a/src/libstd/old_io/net/udp.rs b/src/libstd/old_io/net/udp.rs
index 9055a089eec..de0752b3619 100644
--- a/src/libstd/old_io/net/udp.rs
+++ b/src/libstd/old_io/net/udp.rs
@@ -47,7 +47,7 @@ use sys_common;
 ///     match socket.recv_from(&mut buf) {
 ///         Ok((amt, src)) => {
 ///             // Send a reply to the socket we received data from
-///             let buf = buf.slice_to_mut(amt);
+///             let buf = &mut buf[..amt];
 ///             buf.reverse();
 ///             socket.send_to(buf, src);
 ///         }