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[on:]

Hi,

I've been trying to create a library class, and I get a compile error in the sketch when trying to access members of an instance, wich class has a no-arg constructor.

This is the library class, wich I've put in the hardware\libraries dir as usual:

This is Test.h:

Code:

#ifndef Test_h
#define Test_h

#include "WProgram.h"


class Test
{

  public:
      
       int testVar;
  
      Test();
      void testMethod();

};

#endif

This is Test.cpp:

Code:

#include "WProgram.h"
#include "Test.h"

Test::Test()
{
      testVar = 1;
}

void Test::testMethod()
{
      testVar = 2;
}

And this is the sketch testing the Test class:

Code:

#include <Test.h>

void setup() {

  Test myTest();
  myTest.testVar = 34;
  myTest.testMethod();

}

void loop() {

}

When compiling the sketch, the compiler says:

In function 'void setup()':
error: request for member 'testVar' in 'myTest', wich is of non-class type 'Test ()()'

This happens when accessing the member variable or the method.

But, when adding an integer parameter to the constructor, it compiles nicely. I suppose that it's a bug, because no-arg constructor should be allowed, isn't it?

Thanks in advance

I forgot to mention that I'm using compiler version 0017

[Reply #1 on:]

It will probably not fix your problem, but remove the WProgram from the cpp.

Some compilers will roduce erratic code if both the header and the source includes the same file.

[Reply #2 on:]

You should be able to instantiate a class with a single no-args constructor using the following syntax:

Code:

#include "WProgram.h"
#include <Test.h>

void setup() {

  Test myTest;  // use constructor with no args
  myTest.testVar = 34;
  myTest.testMethod();

}

[Reply #3 on:]

It worked, thanks.