Array of functions?

Projects Programming
1

Is it possible to write an Array of functions? I have a 3x3x3 LED cube and I wrote a function for each LED.

void led1(){
topLayer();
digitalWrite(2, HIGH);
delayMicroseconds(speedTime);
digitalWrite(2, LOW);
delayMicroseconds(lowtime);
}
void led2(){
topLayer();
digitalWrite(4, HIGH);
delayMicroseconds(speedTime);
digitalWrite(4, LOW);
delayMicroseconds(lowtime);
}
void led3(){
topLayer();
digitalWrite(7, HIGH);
delayMicroseconds(speedTime);
digitalWrite(7, LOW);
delayMicroseconds(lowtime);
}
... and so on.

Is it possible to have an array of functions
ledArray[]={led1,led2,led16,led15,led13...};

2

yes:

#define NUMBER_OF_FUNCTIONS 3

void (*myFunction[NUMBER_OF_FUNCTIONS])();

void setup()   
{
  myFunction[0] = functionZero;
  myFunction[1] = functionOne;
  myFunction[2] = functionTwo;
}

void loop()
{
 for (int i = 0; i < NUMBER_OF_FUNCTIONS; i++)
 {
   myFunction[i];
 }
}

void functionZero()
{
}

void functionOne()
{
}

void functionTwo()
{
}
3

but sometimes you only need a parameter for one function instead of an array of functions

int ledpin = { 2, 4, 7 , 9, 10 };
...
void led(int pin)
{
  topLayer();
  digitalWrite(pin, HIGH);
  delayMicroseconds(speedTime);
  digitalWrite(pin, LOW);
  delayMicroseconds(lowtime);  
}

for (int i =0; i < 5; i++) led( ledpin[i] );
4

Although in C++, you'd typically use a polymorphic class for this type of thing:

class ThingDoer {
  public:
    virtual void doThing();
};

class Do1 : public ThingDoer {
    void doThing() {}
};

class Do2 : public ThingDoer {
  public:
    const char *s;
    Do2(const char *s) : s(s) {}
    void doThing() {}
};

class Do3 : public ThingDoer {
  public:
    const int howToDo;
    Do3(int howToDo) : howToDo(howToDo) {}
    void doThing() {}
};


ThingDoer *things[] = {
  new Do1(),
  new Do2("Some Text"),
  new Do1(),
  new Do3(5),
};

int theThing = 0;

void setup() {
}

void loop() {
  things[theThing++]->doThing();
  if (theThing > sizeof(things) / sizeof(*things)) {
    theThing = 0;
  }
}