You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: reader.go
    path of file: ./repos/sliver/implant/vendor/gopkg.in/jcmturner/rpc.v1/mstypes
    
    the code of the file until where you have to start completion: package mstypes

import (
	"bufio"
	"encoding/binary"
	"fmt"
	"io"
)

// Byte sizes of primitive types
const (
	Size
    
func (r *Reader) UTF16String(n int) (str string, err error) {
	//Length divided by 2 as each run is 16bits = 2bytes
	s := make([]rune, n/2, n/2)
	for i := 0; i < len(s); i++ {
		var u uint16
		u, err = r.Uint16()
		if err != nil {
			return
		}
		s[i] = rune(u)
	}
	str = string(s)
	return
}