Add HasNoTokens

contracts/ownership/HasNoTokens.sol

@@ -0,0 +1,26 @@
+pragma solidity ^0.4.8;
+
+import "./Ownable.sol";
+import "../token/ERC20Basic.sol";
+
+/// @title Contracts that should not own Tokens
+/// @author Remco Bloemen <remco@2π.com>
+///
+/// This blocks incoming ERC23 tokens to prevent accidental
+/// loss of tokens. Should tokens (any ERC20Basic compatible)
+/// end up in the contract, it allows the owner to reclaim
+/// the tokens.
+contract HasNoTokens is Ownable {
+
+  /// Reject all ERC23 compatible tokens
+  function tokenFallback(address from_, uint value_, bytes data_) external {
+    throw;
+  }
+
+  /// Reclaim all ERC20Basic compatible tokens
+  function reclaimToken(address tokenAddr) external onlyOwner {
+    ERC20Basic tokenInst = ERC20Basic(tokenAddr);
+    uint256 balance = tokenInst.balanceOf(this);
+    tokenInst.transfer(owner, balance);
+  }
+}