Added functions to Hash & Address

* Set, SetString, SetBytes
* StringTo*, BytesTo*

common/types.go

@@ -5,6 +5,25 @@ type (
 	Address [20]byte
 )
 
+var (
+	zeroHash    Hash
+	zeroAddress Address
+)
+
+func BytesToHash(b []byte) Hash {
+	var h Hash
+	h.SetBytes(b)
+	return h
+}
+func StringToHash(s string) Hash { return BytesToHash([]byte(s)) }
+
+func BytesToAddress(b []byte) Address {
+	var a Address
+	a.SetBytes(b)
+	return a
+}
+func StringToAddress(s string) Address { return BytesToAddress([]byte(s)) }
+
 // Don't use the default 'String' method in case we want to overwrite
 
 // Get the string representation of the underlying hash
@@ -24,8 +43,16 @@ func (h Hash) SetBytes(b []byte) {
 	}
 }
 
+// Set string `s` to h. If s is larger than len(h) it will panic
 func (h Hash) SetString(s string) { h.SetBytes([]byte(s)) }
 
+// Sets h to other
+func (h Hash) Set(other Hash) {
+	for i, v := range other {
+		h[i] = v
+	}
+}
+
 // Get the string representation of the underlying address
 func (a Address) Str() string {
 	return string(a[:])
@@ -42,4 +69,13 @@ func (a Address) SetBytes(b []byte) {
 		a[i] = b[i]
 	}
 }
-func (a Address) SetString(s string) { h.SetBytes([]byte(a)) }
+
+// Set string `s` to a. If s is larger than len(a) it will panic
+func (a Address) SetString(s string) { a.SetBytes([]byte(s)) }
+
+// Sets a to other
+func (a Address) Set(other Address) {
+	for i, v := range other {
+		a[i] = v
+	}
+}