Initial dract of the common structs

common/account.go

@@ -0,0 +1,18 @@
+package common
+
+import (
+	"math/big"
+
+	eth "github.com/ethereum/go-ethereum/common"
+	"github.com/iden3/go-iden3-crypto/babyjub"
+)
+
+// Account is a struct that gives information of the holdings of an address for a specific token
+type Account struct {
+	EthAddr   eth.Address
+	TokenID   TokenID  // effective 32 bits
+	Idx       uint32   // bits = SMT levels (SMT levels needs to be decided)
+	Nonce     uint64   // effective 48 bits
+	Balance   *big.Int // Up to 192 bits
+	Signature babyjub.PublicKey
+}