Question

So I can’t use initializers in my class constructor because of using arrays, so I decided to use an init() method instead. Now I have a different problem. I have a class like this:

class EPWM {
private:
   volatile EPWM_REGS* const regs;
public:
   void init(volatile EPWM_REGS* _regs);
};

where I need to implement init() by initializing regs = _regs; but I can’t because of the const. Is there a way to force the assignment in my init method? I would like to keep the const keyword so I don’t accidentally reassign elsewhere.

edit: as much as I would like to use a constructor + initializer, which would solve this problem (my code used to do this), I cannot because I have another class which has an array of EPWM objects, and I can’t initialize those objects because C++ does not support initializers for array members. (again, see the other question I asked a little while ago on this subject.)

Context for using EPWM is something like this:

class PwmGroup {
private:
   EPWM *epwm;

   void init(EPWM *_epwm) { epwm = _epwm; }
};

/* ... */
// main code:

EPWM epwm[3];
PwmGroup pwmGroup;

{
   // EPwm1Regs, EPwm2Regs, EPwm3Regs are structs
   // defined by TI's include files for this processor
   epwm[0].init(&EPwm1Regs);
   epwm[1].init(&EPwm2Regs);
   epwm[2].init(&EPwm3Regs);
   pwmGroup.init(epwm);
}

Answer 1

You could consider const_cast and pointers, but it’s something best used very rarely. Something like…

EPWM_REGS** regsPP = const_cast<EPWM_REGS**>(&regs);
*regsPP = _regs;