From 8657bc8b8259ae123634a0ca2fe7a8751a75a870 Mon Sep 17 00:00:00 2001
From: poma <Semenov.Roman@mail.ru>
Date: Mon, 15 Jul 2019 19:15:06 +0300
Subject: [PATCH] isSpent function

---
 contracts/Mixer.sol | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/contracts/Mixer.sol b/contracts/Mixer.sol
index 3bf4027..6c3412e 100644
--- a/contracts/Mixer.sol
+++ b/contracts/Mixer.sol
@@ -69,4 +69,8 @@ contract Mixer is MerkleTreeWithHistory {
     }
     emit Withdraw(receiver, nullifier, fee);
   }
+
+  function isSpent(uint256 nullifier) public view returns(bool) {
+    return nullifiers[nullifier];
+  }
 }