Auto merge of #21677 - japaric:no-range, r=alexcrichton

Note: Do not merge until we get a newer snapshot that includes #21374

There was some type inference fallout (see 4th commit) because type inference with `a..b` is not as good as with `range(a, b)` (see #21672).

r? @alexcrichton 

1 files changed, 2 insertions, 2 deletions

diff --git a/src/rustbook/error.rs b/src/rustbook/error.rs
index d4829a2c391..1c10a270acc 100644
--- a/src/rustbook/error.rs
+++ b/src/rustbook/error.rs
@@ -11,7 +11,7 @@
 //! Error handling utilities. WIP.
 
 use std::fmt;
-use std::fmt::{Show, Formatter};
+use std::fmt::{Debug, Formatter};
 
 use std::old_io::IoError;
 
@@ -32,7 +32,7 @@ pub trait FromError<E> {
     fn from_err(err: E) -> Self;
 }
 
-impl Show for Box<Error + 'static> {
+impl Debug for Box<Error + 'static> {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         write!(f, "{}", self.description())
     }