'class X' has no member 'Y'
This error is inexplicably occurring. Here is the code and output:
timer.cpp:
#include "timer.h"
#include "SDL.h"
#include "SDL_timer.h"
void cTimer::recordCurrentTime()
{
this->previous_t = this->current_t;
this->current_t = SDL_GetTicks();
}
timer.h:
#include "SDL.开发者_如何学JAVAh"
#include "SDL_timer.h"
class cTimer
{
private:
int previous_t;
int current_t;
float delta_time;
float accumulated_time;
int frame_counter;
public:
void recordCurrentTime();
float getDelta();
void incrementAccumulator();
void decrementAccumulator();
bool isAccumulatorReady();
void incrementFrameCounter();
void resetFrameCounter();
int getFPS();
};
Compiler errors:
make g++ -Wall -I/usr/local/include/SDL -c timer.cpp timer.cpp: In member function ‘void cTimer::recordCurrentTime()’: timer.cpp:6: error: ‘class cTimer’ has no member named ‘previous_t’ timer.cpp:6: error: ‘class cTimer’ has no member named ‘current_t’ timer.cpp:7: error: ‘class cTimer’ has no member named ‘current_t’ make: *** [timer.o] Error 1
Compiler errors after removing the #include "timer.h"
g++ -Wall -I/usr/local/include/SDL -c ctimer.cpp ctimer.cpp:4: error: ‘cTimer’ has not been declared ctimer.cpp: In function ‘void recordCurrentTime()’: ctimer.cpp:5: error: invalid use of ‘this’ in non-member function ctimer.cpp:5: error: invalid use of ‘this’ in non-member function ctimer.cpp:6: error: invalid use of ‘this’ in non-member function make: *** [ctimer.o] Error 1
Works for me. Are you sure you've got the right timer.h
? Try this:
cat timer.h
and verify that it's what you think it is. If so, try adding ^__^
at the beginning of your .h
file and seeing if you get a syntax error. It should look something like this:
[/tmp]> g++ -Wall -I/tmp/foo -c timer.cpp
In file included from timer.cpp:1:
timer.h:1: error: expected unqualified-id before ‘^’ token
This seems very odd as
class cTimer
{
private:
int previous_t;
int current_t;
float delta_time;
float accumulated_time;
int frame_counter;
public:
void recordCurrentTime();
float getDelta();
void incrementAccumulator();
void decrementAccumulator();
bool isAccumulatorReady();
void incrementFrameCounter();
void resetFrameCounter();
int getFPS();
};
void cTimer::recordCurrentTime()
{
this->previous_t = this->current_t;
this->current_t = SDL_GetTicks();
}
Compiles OK for me.
This suggests that the compiler think cTimer is different from what you've put in your header. So maybe its getting a definition of cTimer from another source file? For this to be the case your "timer.h" would have to not be gettting included correctly. So maybe the wrong timer.h.
A way to check this would be to save the compiler preprocessor output and search that for cTimer.
Another option might be to put a syntax error in your timer.h and make sure the compile fails.
Anyway hope this helps
Some compilers have their own timer.h, this is a name conflict.
Or it is a something else of bizarre bug...
Try renaming timer.h and timer.cpp to something more descriptive like ClassTimer.h and ClassTimer.cpp, maybe the compiler is linking another file named 'timer' since it is a very generic name. Also try this in timer.cpp:
void cTimer::recordCurrentTime(void)
{
this->previous_t = this->current_t;
this->current_t = SDL_GetTicks();
}
Edit: code edited
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