adding Bytes() to MaskBit

bitmask/bitmask.go

@@ -1,5 +1,12 @@
 package bitmask
 
+import (
+	"bytes"
+	"errors"
+	"encoding/binary"
+	"math/bits"
+)
+
 // MaskBit is a flag container.
 type MaskBit uint
 
@@ -62,6 +69,46 @@ func (m *MaskBit) ToggleFlag(flag MaskBit) {
 	return
 }
 
+/*
+	Bytes returns the current value of a MasBit as a byte slice (big-endian).
+
+	If trim is false, b will (probably) be 4 bytes long if you're on a 32-bit size system,
+	and b will (probably) be 8 bytes long if you're on a 64-bit size system. You can determine
+	the size of the resulting slice via (math/)bits.UintSize / 8.
+
+	If trim is true, it will trim leading null bytes (if any). This will lead to an unpredictable
+	byte slice length in b, but is most likely preferred for byte operations.
+
+*/
+func (m *MaskBit) Bytes(trim bool) (b []byte) {
+
+	var b2 []byte
+	var size int = bits.UintSize / 8
+	var err error
+
+	b2 = make([]byte, size)
+
+	switch s := bits.UintSize; s {
+	case 32:
+		binary.BigEndian.PutUint32(b2[:], uint32(*m))
+	case 64:
+		binary.BigEndian.PutUint64(b2[:], uint64(*m))
+	default:
+		err = errors.New("unsupported Uint/system bit size")
+		panic(err)
+	}
+
+	if trim {
+		b = bytes.TrimLeft(b2, "\x00")
+		return
+	} else {
+		b = b2
+		return
+	}
+
+	return
+}
+
 // Value returns the current raw uint value of a MaskBit.
 func (m *MaskBit) Value() (v uint) {