Updates to Solidity 0.6.4

contracts/MerklePatriciaProof.sol

@@ -16,7 +16,7 @@ library MerklePatriciaProof {
      * @param root The root hash of the trie.
      * @return The boolean validity of the proof.
      */
-    function verify(bytes value, bytes encodedPath, bytes rlpParentNodes, bytes32 root) internal constant returns (bool) {
+    function verify(bytes memory value, bytes memory encodedPath, bytes memory rlpParentNodes, bytes32 root) internal pure returns (bool) {
         RLP.RLPItem memory item = RLP.toRLPItem(rlpParentNodes);
         RLP.RLPItem[] memory parentNodes = RLP.toList(item);
 
@@ -71,7 +71,7 @@ library MerklePatriciaProof {
         }
     }
 
-    function _nibblesToTraverse(bytes encodedPartialPath, bytes path, uint pathPtr) private constant returns (uint) {
+    function _nibblesToTraverse(bytes memory encodedPartialPath, bytes memory path, uint pathPtr) private pure returns (uint) {
         uint len;
         // encodedPartialPath has elements that are each two hex characters (1 byte), but partialPath
         // and slicedPath have elements that are each one hex character (1 nibble)
@@ -94,7 +94,7 @@ library MerklePatriciaProof {
     }
 
     // bytes b must be hp encoded
-    function _getNibbleArray(bytes b) private constant returns (bytes) {
+    function _getNibbleArray(bytes memory b) private pure returns (bytes memory) {
         bytes memory nibbles;
         if(b.length>0) {
             uint8 offset;
@@ -116,7 +116,7 @@ library MerklePatriciaProof {
         return nibbles;
     }
 
-    function _getNthNibbleOfBytes(uint n, bytes str) private constant returns (byte) {
+    function _getNthNibbleOfBytes(uint n, bytes memory str) private pure returns (byte) {
         return byte(n%2==0 ? uint8(str[n/2])/0x10 : uint8(str[n/2])%0x10);
     }
 }