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: iter_object.go
    path of file: ./repos/devspace/vendor/github.com/json-iterator/go
    
    the code of the file until where you have to start completion: package jsoniter

import (
	"fmt"
	"strings"
)

// ReadObject read one field from object.
// If object ended, returns empty string.
// Otherwise, returns the field name.
func (iter *Iterator) ReadObject() (ret string) {
	c := iter.nextToken()
	switch c {
	case 'n':
		iter.skipThreeBytes('u', 'l', 'l')
		return "" // null
	case '{':
		c = iter.nextToken()
		if c == '"' {
			iter.unreadByte()
			field := iter.ReadString()
			c = iter.nextToken()
			if c != ':' {
				iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
			}
			return field
		}
		if c == '}' {
			return "" // end of object
		}
		iter.ReportError("ReadObject", `expect " after {, but found `+string([]byte{c}))
		return
	case ',':
		field := iter.ReadString()
		c = iter.nextToken()
	
    
func (iter *Iterator) ReadObjectCB(callback func(*Iterator, string) bool) bool {
	c := iter.nextToken()
	var field string
	if c == '{' {
		if !iter.incrementDepth() {
			return false
		}
		c = iter.nextToken()
		if c == '"' {
			iter.unreadByte()
			field = iter.ReadString()
			c = iter.nextToken()
			if c != ':' {
				iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
			}
			if !callback(iter, field) {
				iter.decrementDepth()
				return false
			}
			c = iter.nextToken()
			for c == ',' {
				field = iter.ReadString()
				c = iter.nextToken()
				if c != ':' {
					iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
				}
				if !callback(iter, field) {
					iter.decrementDepth()
					return false
				}
				c = iter.nextToken()
			}
			if c != '}' {
				iter.ReportError("ReadObjectCB", `object not ended with }`)
				iter.decrementDepth()
				return false
			}
			return iter.decrementDepth()
		}
		if c == '}' {
			return iter.decrementDepth()
		}