C++ STL: Can arrays be used transparently with STL functions?

Question

I was under the assumption that STL functions could be used only with STL data containers (like vector) until I saw this piece of code:

#include         


        

Answer 1

the STL has it hidden stuff. Most of this works thanks to iterators, consider this code:

std::vector a = {0,1,2,3,4,5,6,7,8,9};
// this will work in C++0x use -std=c++0x with gcc
// otherwise use push_back()

// the STL will let us create an array from this no problem
int * array = new int[a.size()];
// normally you could 'iterate' over the size creating
// an array from the vector, thanks to iterators you
// can perform the assignment in one call
array = &(*a.begin());

// I will note that this may not be considered an array
// to some. because it's only a pointer to the vector.
// However it comes in handy when interfacing with C
// Instead of copying your vector to a native array
// to pass to a C function that accepts an int * or
// anytype for that matter, you can just pass the
// vector's iterators .begin().

// consider this C function
extern "C" passint(int *stuff) { ... }

passint(&(*a.begin())); // this is how you would pass your data.

// lets not forget to delete our allocated data
delete[] a;