restore standard library features

Author: joel-ling

binary.go

@@ -1,7 +1,9 @@
 package binary
 
 import (
+	stdlib "encoding/binary"
 	"fmt"
+	"io"
 
 	"github.com/encodingx/binary/internal/validation"
 )
@@ -85,3 +87,62 @@ func Unmarshal(bytes []byte, iface interface{}) (e error) {
 
 	return
 }
+
+// Standard library features
+
+const (
+	MaxVarintLen16 = stdlib.MaxVarintLen16
+	MaxVarintLen32 = stdlib.MaxVarintLen32
+	MaxVarintLen64 = stdlib.MaxVarintLen64
+)
+
+var (
+	BigEndian    = stdlib.BigEndian
+	LittleEndian = stdlib.LittleEndian
+)
+
+type ByteOrder interface {
+	Uint16([]byte) uint16
+	Uint32([]byte) uint32
+	Uint64([]byte) uint64
+	PutUint16([]byte, uint16)
+	PutUint32([]byte, uint32)
+	PutUint64([]byte, uint64)
+	String() string
+}
+
+func PutUvarint(buf []byte, x uint64) int {
+	return stdlib.PutUvarint(buf, x)
+}
+
+func PutVarint(buf []byte, x int64) int {
+	return stdlib.PutVarint(buf, x)
+}
+
+func Read(r io.Reader, order ByteOrder, data interface{}) error {
+	return stdlib.Read(r, order, data)
+}
+
+func ReadUvarint(r io.ByteReader) (uint64, error) {
+	return stdlib.ReadUvarint(r)
+}
+
+func ReadVarint(r io.ByteReader) (int64, error) {
+	return stdlib.ReadVarint(r)
+}
+
+func Size(v interface{}) int {
+	return stdlib.Size(v)
+}
+
+func Uvarint(buf []byte) (uint64, int) {
+	return stdlib.Uvarint(buf)
+}
+
+func Varint(buf []byte) (int64, int) {
+	return stdlib.Varint(buf)
+}
+
+func Write(w io.Writer, order ByteOrder, data interface{}) error {
+	return stdlib.Write(w, order, data)
+}

metadata-format.go

@@ -53,6 +53,9 @@ func newFormatMetadataFromTypeReflection(reflection reflect.Type) (
 }
 
 func (m formatMetadata) marshal(reflection reflect.Value) (bytes []byte) {
+	// Merge byte slices marshalled from words,
+	// in the order they appear in the format.
+
 	var (
 		copyIndex int
 		i         int