util reexports less std

ethcore/src/state/account.rs

@@ -16,6 +16,8 @@
 
 //! Single account in the system.
 
+use std::fmt;
+use std::collections::HashMap;
 use util::*;
 use pod_account::*;
 use rlp::*;

ethcore/src/state/mod.rs

@@ -21,6 +21,8 @@
 
 use std::cell::{RefCell, RefMut};
 use std::collections::hash_map::Entry;
+use std::collections::{HashMap, BTreeMap, HashSet};
+use std::fmt;
 
 use receipt::Receipt;
 use engines::Engine;