Correct formatting docs: fmt::Result != io::Result<()>

Author: Stebalien

src/libcollections/fmt.rs

@@ -165,9 +165,9 @@
 //! provides some helper methods.
 //!
 //! Additionally, the return value of this function is `fmt::Result` which is a
-//! typedef to `Result<(), std::io::Error>` (also known as `std::io::Result<()>`).
-//! Formatting implementations should ensure that they return errors from `write!`
-//! correctly (propagating errors upward).
+//! typedef to `Result<(), std::fmt::Error>`. Formatting implementations should
+//! ensure that they return errors from `write!` correctly (propagating errors
+//! upward).
 //!
 //! An example of implementing the formatting traits would look
 //! like: