diff --git a/src/tokenizer/interface.rs b/src/tokenizer/interface.rs
index d06094a2..d9b86d9c 100644
--- a/src/tokenizer/interface.rs
+++ b/src/tokenizer/interface.rs
@@ -13,7 +13,6 @@ use core::clone::Clone;
 use tokenizer::states;
 
 use collections::vec::Vec;
-use collections::slice::SliceExt;
 use collections::string::String;
 use std::borrow::Cow;
 use std::marker::Send;
diff --git a/src/tokenizer/mod.rs b/src/tokenizer/mod.rs
index afc54e90..09e26182 100644
--- a/src/tokenizer/mod.rs
+++ b/src/tokenizer/mod.rs
@@ -39,9 +39,7 @@ use core::mem::replace;
 use core::default::Default;
 use alloc::boxed::Box;
 use collections::vec::Vec;
-use collections::slice::SliceExt;
 use collections::string::{String, ToString};
-use collections::str::StrExt;
 use std::borrow::Cow::{self, Borrowed};
 use std::collections::BTreeMap;
 
diff --git a/src/util/str.rs b/src/util/str.rs
index ec6a4f9f..892d9707 100644
--- a/src/util/str.rs
+++ b/src/util/str.rs
@@ -14,7 +14,6 @@ use collections::string::String;
 use core::fmt::Debug;
 
 pub fn to_escaped_string<T: Debug>(x: &T) -> String {
-    use collections::str::StrExt;
     use core::fmt::Write;
 
     // FIXME: don't allocate twice