What are the major differences between C and C++ and when would you choose one over the other?

Question

For those of you with experience with both, what are the major differences? For a newcomer to either, which would be better to learn? Are there situations where you might choose C but then other situations where you would choose C++? Is it a case of use the best tool for the job or one is significantly better than the other. I know C++ is an "enhancement" of C, but it was created in '83 and hasn't completely replaced C so there must be something more to it.

I know this question is subjective and I am not trying to start any religious war, so please try to be as objective as possible. Clear strengths and weaknesses and comparisons.

Answer 1

While C is a pure procedural language, C++ is a multi-paradigm language. It supports

• Generic programming: Allowing to write code once, and use it with different data-structures.
• Meta programming: Allowing to utilize templates to generate efficient code at compile time.
• Inspection: Allows to inspect certain properties at compile time: What type does an expression have? How many parameters does a function have? What type does each one have?
• Object oriented programming: Allowing the programmer to program object oriented, with sophisticated features such as multiple inheritance and private inheritance.
• Procedural programming: Allows the programmer to put functions free of any classes. Combined with advanced features such as ADL allows writing clean code decoupled from specifics of certain classes.

Apart from those, C++ has largely kept compatibility with C code, but there are some differences. Those can be read about in Annex D of the C++ Standard, together with reasons and possible fixed to make C code valid C++ code.

Answer 2

C++ is 99% a superset of C. It's a little more strict in syntax, with a few very minute differences in terms of things changing.

The biggest difference is that C++ makes an attempt at being object oriented. There's native support for classes.

There's a few other perks in C++: templates, stream operators, pass-by-reference (a bit less confusing than pass-by-pointer)

What do you lose out for going C++? It's missing some of the lowest-level hacks that a lot of people use C for. I don't remember any of them offhand, but I've never heard any good argument for tricking the compiler into doing what you want except as a way to push efficiency that extra 10%.