How to Choose Function Based on Loop Iterator - c++

Question

Part of my problem in finding a solution here is likely that I don't know the correct terms for what it is I am asking. For that, I beg forgiveness in advance.
For a microcontroller, I have a list of pins I wish to initiate at the same time. Each has it's own ISR, and calls the same member of a class for each instance but with a pin number as an argument.
I am trying to attach each pin in the array to its corresponding ISR but I would like to choose which ISR by the pin's index. This is Mailer Code™ and likely does not compile but I believe it's enough to get the idea:
#define PIN1 4
#define PIN2 9
#define PIN3 10
#define PIN4 8
#define PIN5 12
PinAct *pPinact; // Pointer to Counter class
static ICACHE_RAM_ATTR void HandleInterruptsStatic1(void) {
pPinact->handleInterrupts(1);
}
static ICACHE_RAM_ATTR void HandleInterruptsStatic2(void) {
pPinact->handleInterrupts(2);
}
static ICACHE_RAM_ATTR void HandleInterruptsStatic3(void) {
pPinact->handleInterrupts(3);
}
static ICACHE_RAM_ATTR void HandleInterruptsStatic4(void) {
pPinact->handleInterrupts(4);
}
static ICACHE_RAM_ATTR void HandleInterruptsStatic5(void) {
pPinact->handleInterrupts(5);
}
class PinAct {
public:
PinAct() {};
void handleInterrupts(int);
}
void PinAct::PinAct() {
int actPins[] = {PIN1, PIN2, PIN3, PIN4, PIN5};
for (int i = 0; i <= sizeof(actPins); i++) {
pinMode(actPin[i], INPUT)
attachInterrupt(digitalPinToInterrupt(KEG1), HandleInterruptsStatic + i, FALLING);
}
}
void PinAct::handleInterrupts(int pin) { // Bubble Interrupt handler
// Do something with pin
}
The goal is to actually make the attachInterrupt(digitalPinToInterrupt(KEG1), HandleInterruptsStatic + i, FALLING); work, choosing which ISR by virtue of the index i.
I need to make other decisions about whether or not to assign the ISR, so concatenating the ISR name to be assigned is desirable.

Answer 1

attachInterrupt(/* ... */, HandleInterruptsStatic + i, /* ... */);
// ^^^^^
In order to select the function you want to call at runtime depending on some integer index i you can use an array of function pointers:
typedef void (*FunctionPointer_t)(void);
FunctionPointer_t functions[] = {
HandleInterruptsStatic1,
HandleInterruptsStatic2,
// ...
};
// to use:
functions[i]();