Updates with core::fmt changes

1. Wherever the `buf` field of a `Formatter` was used, the `Formatter` is used
   instead.
2. The usage of `write_fmt` is minimized as much as possible, the `write!` macro
   is preferred wherever possible.
3. Usage of `fmt::write` is minimized, favoring the `write!` macro instead.

1 files changed, 2 insertions, 2 deletions

diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index 497213df30f..a043722581b 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -381,9 +381,9 @@ impl IoError {
 
 impl fmt::Show for IoError {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        try!(fmt.buf.write_str(self.desc));
+        try!(write!(fmt, "{}", self.desc));
         match self.detail {
-            Some(ref s) => write!(fmt.buf, " ({})", *s),
+            Some(ref s) => write!(fmt, " ({})", *s),
             None => Ok(())
         }
     }