Merge pull request #41 from gavofyork/bytes_ref

bytes_ref

src/bytes.rs

@@ -39,6 +39,7 @@ use std::fmt;
 use std::slice;
 use std::cmp::Ordering;
 use std::error::Error as StdError;
+use std::ops::{Deref, DerefMut};
 use uint::{U128, U256};
 use hash::FixedHash;
 
@@ -89,6 +90,31 @@ impl ToPretty for Bytes {
 	}
 }
 
+pub enum BytesRef<'a> {
+	Flexible(&'a mut Bytes),
+	Fixed(&'a mut [u8])
+}
+
+impl<'a> Deref for BytesRef<'a> {
+	type Target = [u8];
+
+	fn deref(&self) -> &[u8] {
+		match self {
+			&BytesRef::Flexible(ref bytes) => bytes,
+			&BytesRef::Fixed(ref bytes) => bytes
+		}
+	}
+}
+
+impl <'a> DerefMut for BytesRef<'a> {
+	fn deref_mut(&mut self) -> &mut [u8] {
+		match self {
+			&mut BytesRef::Flexible(ref mut bytes) => bytes,
+			&mut BytesRef::Fixed(ref mut bytes) => bytes
+		}
+	}
+}
+
 /// Vector of bytes
 pub type Bytes = Vec<u8>;
 
@@ -436,4 +462,4 @@ fn populate_big_types() {
 	let mut h = h256_from_u64(0x69);
 	h.copy_raw_from(&a);
 	assert_eq!(h, h256_from_hex("ffffffffffffffffffffffffffffffffffffffff000000000000000000000069"));
-}
+}