4 files changed, 8 insertions, 7 deletions
diff --git a/src/libstd/io/mod.rs b/src/libstd/io/mod.rs
index dbf61b132e0..233ad781093 100644
--- a/src/libstd/io/mod.rs
+++ b/src/libstd/io/mod.rs
@@ -242,10 +242,11 @@ use result::Result;
 use result::Result::{Ok, Err};
 use sys;
 use slice::SliceExt;
-use str::StrPrelude;
+use str::StrExt;
 use str;
 use string::String;
 use uint;
+use unicode;
 use unicode::char::UnicodeChar;
 use vec::Vec;
 
@@ -1505,7 +1506,7 @@ pub trait Buffer: Reader {
     /// valid utf-8 encoded codepoint as the next few bytes in the stream.
     fn read_char(&mut self) -> IoResult<char> {
         let first_byte = try!(self.read_byte());
-        let width = str::utf8_char_width(first_byte);
+        let width = unicode::str::utf8_char_width(first_byte);
         if width == 1 { return Ok(first_byte as char) }
         if width == 0 { return Err(standard_error(InvalidInput)) } // not utf8
         let mut buf = [first_byte, 0, 0, 0];
@@ -1519,7 +1520,7 @@ pub trait Buffer: Reader {
                 }
             }
         }
-        match str::from_utf8(buf[..width]) {
+        match str::from_utf8(buf[..width]).ok() {
             Some(s) => Ok(s.char_at(0)),
             None => Err(standard_error(InvalidInput))
         }
diff --git a/src/libstd/io/net/ip.rs b/src/libstd/io/net/ip.rs
index 71776b6c46a..89a649d55bd 100644
--- a/src/libstd/io/net/ip.rs
+++ b/src/libstd/io/net/ip.rs
@@ -25,8 +25,8 @@ use ops::FnOnce;
 use option::Option;
 use option::Option::{None, Some};
 use result::Result::{Ok, Err};
-use str::{FromStr, StrPrelude};
 use slice::{CloneSliceExt, SliceExt};
+use str::{FromStr, StrExt};
 use vec::Vec;
 
 pub type Port = u16;
diff --git a/src/libstd/io/process.rs b/src/libstd/io/process.rs
index 9da1117f227..4a0a3936424 100644
--- a/src/libstd/io/process.rs
+++ b/src/libstd/io/process.rs
@@ -1082,7 +1082,7 @@ mod tests {
 
         let prog = env_cmd().env_set_all(new_env.as_slice()).spawn().unwrap();
         let result = prog.wait_with_output().unwrap();
-        let output = String::from_utf8_lossy(result.output.as_slice()).into_string();
+        let output = String::from_utf8_lossy(result.output.as_slice()).to_string();
 
         assert!(output.contains("RUN_TEST_NEW_ENV=123"),
                 "didn't find RUN_TEST_NEW_ENV inside of:\n\n{}", output);
@@ -1092,7 +1092,7 @@ mod tests {
     fn test_add_to_env() {
         let prog = env_cmd().env("RUN_TEST_NEW_ENV", "123").spawn().unwrap();
         let result = prog.wait_with_output().unwrap();
-        let output = String::from_utf8_lossy(result.output.as_slice()).into_string();
+        let output = String::from_utf8_lossy(result.output.as_slice()).to_string();
 
         assert!(output.contains("RUN_TEST_NEW_ENV=123"),
                 "didn't find RUN_TEST_NEW_ENV inside of:\n\n{}", output);
diff --git a/src/libstd/io/stdio.rs b/src/libstd/io/stdio.rs
index 36dd5492356..1c5ceaf2450 100644
--- a/src/libstd/io/stdio.rs
+++ b/src/libstd/io/stdio.rs
@@ -43,7 +43,7 @@ use ops::{Deref, DerefMut, FnOnce};
 use result::Result::{Ok, Err};
 use rt;
 use slice::SliceExt;
-use str::StrPrelude;
+use str::StrExt;
 use string::String;
 use sys::{fs, tty};
 use sync::{Arc, Mutex, MutexGuard, Once, ONCE_INIT};