Working with String Views

Pitfalls of std::string_view

What are the potential pitfalls of using std::string_view?

Abstract art representing computer programming

std::string_view is a powerful tool in C++, offering benefits such as efficient string handling without the overhead of copying. However, it comes with some pitfalls that developers need to be aware of.

Dangling References

One of the primary risks is dangling references. Since std::string_view does not own the underlying string, it can easily reference invalid memory if the original string is modified or destroyed. For example:

#include <iostream>
#include <string_view>

int main() {
  std::string_view view;
    std::string str{"Hello, World!"};
    view = std::string_view{str};
  }  // str is destroyed here

  std::cout << view;  
undefined behavior or runtime error

In this example, view points to a string that has been destroyed, leading to undefined behavior.

Null-Terminated Strings

std::string_view does not ensure the underlying string is null-terminated. Functions expecting null-terminated strings, like many C APIs, can misbehave if passed a std::string_view:

#include <iostream>
#include <string_view>
#include <cstring>

int main() {
  std::string_view view{"Hello"};
  std::cout << std::strlen(;  
undefined behavior

Here, may not point to a null-terminated string, causing std::strlen to read out of bounds.

Immutable Strings

std::string_view treats the underlying string as immutable. If you need to modify the string, you must convert it back to a modifiable type, such as std::string. This conversion incurs overhead and might not be efficient for frequent modifications.

Lifetime Management

Ensuring that the lifetime of the underlying string outlasts the std::string_view can be tricky, especially in complex applications. It's easy to accidentally reference a temporary string, leading to subtle bugs.


Despite its pitfalls, std::string_view is incredibly useful for efficient string handling.

However, developers must carefully manage the lifetime of the underlying string, avoid passing std::string_view to functions expecting null-terminated strings, and remember that std::string_view provides a read-only view.

Answers to questions are automatically generated and may not have been reviewed.

Free, Unlimited Access

Professional C++

Comprehensive course covering advanced concepts, and how to use them on large-scale projects.

Screenshot from Warhammer: Total War
Screenshot from Tomb Raider
Screenshot from Jedi: Fallen Order
Contact|Privacy Policy|Terms of Use
Copyright © 2024 - All Rights Reserved