From 6447f9b90bde28a9851605730899e661ace850ad Mon Sep 17 00:00:00 2001
From: Gav Wood <gav@ethcore.io>
Date: Wed, 13 Jan 2016 01:18:33 +0100
Subject: [PATCH] Additional helper function.

---
 src/json_aid.rs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/json_aid.rs b/src/json_aid.rs
index ccfdee490..a382c61ec 100644
--- a/src/json_aid.rs
+++ b/src/json_aid.rs
@@ -35,8 +35,7 @@ pub fn h256_from_json(json: &Json) -> H256 {
 	}
 }
 
-pub fn u256_from_json(json: &Json) -> U256 {
-	let s = json.as_string().unwrap_or("");
+pub fn u256_from_hex(s: &str) -> U256 {
 	if s.len() >= 2 && &s[0..2] == "0x" {
 		U256::from_str(&s[2..]).unwrap_or(U256::from(0))
 	} else {
@@ -44,6 +43,10 @@ pub fn u256_from_json(json: &Json) -> U256 {
 	}
 }
 
+pub fn u256_from_json(json: &Json) -> U256 {
+	u256_from_hex(json.as_string().unwrap_or(""))
+}
+
 pub fn usize_from_json(json: &Json) -> usize {
 	u256_from_json(json).low_u64() as usize
 }