Why enum?

[NoobsDeSroobs]

enum can be used to give a "name" a value.

like

enum
{
    keyUp, // gives "keyUp" the value 0
    keyDown,  // gives "keyDown" the value 1
    keyLeft,  // gives "keyLeft" the value 2 
    keyRight  // gives "keyRight" the value 3
};

This can be done like this too:

int keyUp = 0;
int keyDown = 1;
int keyLeft = 2;
int keyRight = 3;

A friend told me it was because a enum value was constant, but you can do that by saying this:

const int keyUp = 0;
const int keyDown = 1;
const int keyLeft = 2;
const int keyRight = 3;

So why use enum?? except that it is less typing?

[smilodon]

The reason why is that anyone else who looks at your code will immediately know what is going on. Second, it reduces the likelihood of mistakes when writing a long enumeration. There are probably others that I cannot think about at the moment.

[NoobsDeSroobs]

so is a enum value a constant value or can it be changed as we like?

[smilodon]

I believe it is a const, but you can always write a program to try it out.

[S6k9GNh0]

Enum are a bunch of constant values that are sequenced. Enums are useful lots of places although difficult to explain. Another reason to use enum is that you can turn an enum into a type.

#include <stdlib.h>

enum KEYS
{
    UP,
    RIGHT,
    DOWN,
    LEFT
};

void (KEYS enumExample)
{
    switch (enumExample)
    {
        case UP:
        case RIGHT:
        case DOWN:
        case LEFT: break;
        default: exit(1);
    }
}

This is the best example I can think of. Here we create a enum type called KEYS. We then make a function parameter with KEYS. This is good because if the developer tries to pass something that isn't inside the KEYS type, it will error out which is a good thing.

[NoobsDeSroobs]

ohh, it became clear now. Thank you so much.