struct or class in Arduino IDE / Avr?

Projects Programming
1

less code, more software

Both struct and class will compile in Arduino IDE , but the above reference is C# specific.

class StateIdle {
  void enter();
  void handle();
} 
state_idle;

struct StateIdle_A {
  void enter();
  void handle();
} 
state_idle_A;

Maybe the above reference it is wrong in that aspect and applies to C++ also. I don't know.
I was under the impression that Arduino IDE is using C++ compiler.
So how does this work / compile in Arduino IDE if struct in plain C could not have functions / methods ?
Was using methods one of the primary features of C++ class?

2

So how does this work / compile in Arduino IDE if struct in plain C could not have functions / methods ?

Because structs in C++ can have methods.

Was using methods one of the primary features of C++ class?

Yes.

3

So how does this work / compile in Arduino IDE if struct in plain C could not have functions / methods ?

It is actually far more complex. You can, with care, mix Arduino with C++ with inline assembler with extern C all at the same time.

Under-the-hood runline options: AVR Options (Using the GNU Compiler Collection (GCC))
AVR LibC home: AVR Libc Home Page
Inline assembler: Inline Assembler Cookbook
And many, many hits on Google...

4

Thanks,
now the follow-up. The C++ class supplies default constructor , so if I use struct with methods does it also creates default constructor? Also at this point I do not see usage for destructor in ATmel but assume that struct would not have one anyway.
I think I will stick with class for a while.

5

classes and structs are equivalent except that classes have private default access specifier while it's public for structs. So yes, structs also have default constructor/destructor/assignment operator generated for them.

Cheers, Jarkko