What Is the Difference Between Structs and Classes in C++?

TL;DR

The difference between structs and classes in C++ lies in their default member visibility: members in a struct are public by default, while members in a class are private. Structs exist for backward compatibility with C, and personal programming style typically influences when to use one over the other.

Transcript

Hey, guys. My name is The Cherno and welcome back to my C++ series. This is going to be a really quick episode in which I'm just going to based answer the question What is the difference between a struct and a class in C++? The last time we talked about classes in General And we had a bit of a basic introduction to what classes actually were you gu... Read More

Key Insights

• 👷 The only difference between a struct and a class in C++ is the default visibility of members.
• 👨‍💻 The struct keyword exists in C++ for backward compatibility with C code.
• 👨‍💻 Personal programming style and preference may dictate the usage of struct and class in code.
• 👷 Inheritance should be used with classes, not structs.
• 🥶 Structs are commonly used for plain old data (POD) structures that represent variables without much functionality.
• 👨‍💻 The compatibility between C and C++ code can be maintained by using a define statement to replace all instances of the struct keyword with class.

Questions & Answers

Q: What is the difference between a struct and a class in C++?

The only difference between a struct and a class in C++ is the default visibility of members. In a struct, members are public by default, while in a class, members are private by default.

Q: Why does the struct keyword exist in C++?

The struct keyword exists in C++ for backward compatibility with C code. C code does not have classes, but it does have structures. Using the struct keyword allows C++ to maintain compatibility with C code.

Q: When should I use a struct instead of a class?

You can use a struct instead of a class when you want all of the members to be public by default and you don't want to explicitly write the word "public". It is typically used for plain old data (POD) structures that represent variables without much functionality.

Q: Can I use a struct and a class interchangeably in C++?

Yes, you can use a struct and a class interchangeably in C++. The only difference is the default visibility of members. You can choose to use either based on personal programming style and preference.

Key Insights:

• The only difference between a struct and a class in C++ is the default visibility of members.
• The struct keyword exists in C++ for backward compatibility with C code.
• Personal programming style and preference may dictate the usage of struct and class in code.
• Inheritance should be used with classes, not structs.
• Structs are commonly used for plain old data (POD) structures that represent variables without much functionality.
• The compatibility between C and C++ code can be maintained by using a define statement to replace all instances of the struct keyword with class.
• Support for the C++ series can be shown by following The Cherno on Twitter and Instagram or supporting them on Patreon.

Summary & Key Takeaways

• The main difference between a struct and a class in C++ is the default visibility of members. In a class, members are private by default, while in a struct, members are public by default.

• The struct keyword exists in C++ for backward compatibility with C code, as C code does not have classes but does have structures.

• The usage of struct and class in code may differ based on personal programming style, but there is no right or wrong answer.