Can I use a boolean as an index?

[ausairman]

vector<int> myvec;
myvec.resize(2);
bool idx1 = false;
bool idx2 = true;

myvec[idx1] = 123;
myvec[idx2] = 456;

Is this OK? The reason I'm asking is that I have a boolean type enum that I want to use to index a vector. I know this example doesn't make it look very elegant but it's the best solution I can think of for my code.

[Bourgond Aries]

vector<int> myvec;
myvec.resize(2);
bool idx1 = false;
bool idx2 = true;

myvec[statc_cast<int>(idx1)] = 123;
myvec[statc_cast<int>(idx2)] = 456;

static_cast<int>(x) will try to cast x into an integer correctly, this makes the code obvious and not implicit, and in many cases, a lot safer (you don't actually write idx1 + 1 later on when you don't remember the type of idx1 and assume it's an integer.

static_cast<int>(true) == 1
static_cast<int>(false) == 0

[MiiNiPaa]

I want to add that conversions true -> 1 and false -> 0 is guaranteed by standard (p. 4.7.4)

[vlad from moscow]

Yes you can. An object of type bool will be implicitly converted to type int. So there is no any problem. You need no explicitly to write static_cast as it was shown. This code is valid

myvec[idx1] = 123;
myvec[idx2] = 456;

[ausairman]

Ok great, thanks :)