// Copyright (c) 2016 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

package atomic

import "sync/atomic"

// String is an atomic type-safe wrapper around atomic.Value for strings.
type String struct{ atomic.Value }

// NewString creates a String.
func NewString(str string) *String {
	s := &String{}
	if str != "" {
		s.Store(str)
	}
	return s
}

// Load atomically loads the wrapped string.
func (s *String) Load() string {
	v := s.Value.Load()
	if v == nil {
		return ""
	}
	return v.(string)
}

// Store atomically stores the passed string.
// Note: Converting the string to an interface{} to store in the atomic.Value
// requires an allocation.
func (s *String) Store(str string) {
	s.Value.Store(str)
}