Question

I am trying to implement a progress bar for a console application in windows using Win32 Console API. My problem is that the compiler gives the error, error C2059: syntax error : 'constant'. The relevant code is as follows.

void updateBar(PBAR * pbr, float ratio){
    COORD pos;
    pos.X = 0;
    pos.Y = 25;

    SetConsoleCursorPosition(hConOut, pos);
}

COORD is the Win32 structure for denoting a co-ordinate pair. hConOut is a global variable and PBAR is a structure. Above error is given twice for two assignments (pos.X = 0 an pox.Y = 25). If I use the following, it compiles perfectly.

void updateBar(PBAR * pbr, float ratio){
    COORD pos = {0, 25};
    SetConsoleCursorPosition(hConOut, pos);
}

I really can’t understand the reason for this. I mean it’s just an assignment to structure members, right ?? If I do something like POINT pt; pt.x = 0; pt.y = 25, it compiles perfectly. POINT is just another structure.

I use visual studio 2010 on windows 7 and compiler is:

Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.30319.01 for 80×86

Any thoughts ?? Thanks in advance.

Answer 1

I compiled this and it works fine.

However, if I define X or Y as macros, e.g.

#define X 2
#define Y 15

then I get exactly the same error as you. Do you have these macros?