Component of the Week #2: `bsl_iterator`

Summary:

Provides free functions like size, begin, and end that work on C-style arrays and array-like types (like vector)

Have you ever wanted to get the size of a C-style array and grown tired of typing sizeof myArray / sizeof *myArray? Or written a function template that needs to work seamlessly with C-style arrays, bsl::vector, bsl::array, etc? There is a BDE component for that! And that component is bsl_iterator.

bsl_iterator contains a bunch of free functions that make such scenarios easier to handle.

bsl::size will get you the container’s size:

int myArray[] = {1, 2, 3};
bsl::cout << bsl::size(myArray);

And it will work just as well for any container that has .size():

bsl::vector<int> vec{1, 2, 3};
bsl::set<int> set{4, 5, 6, 6};
bsl::cout << bsl::size(vec) << " " << bsl::size(set);

If you want the size converted to appropriate signed type, there’s bsl::ssize:

bsl::vector<int> vec{1, 2, 3};
for (auto i = bsl::ssize(vec) - 1; i >= 0; --i) {
    bsl::cout << vec[i] << '\n';
}

Need to get iterators for C-style arrays and containers in a uniform manner? You have bsl::begin, bsl::end, and their const and reverse variants (e.g., bsl::crbegin that gives you a const reverse begin iterator):

bsl::array arr{1, 2, 3};

for (auto it = bsl::crbegin(arr); it != bsl::crend(arr); ++it) {
    bsl::cout << *it << '\n';
}

And so much more! Check out the documentation for bsl_iterator.

Component of the Week #2: bsl_iterator

Component of the Week #2: `bsl_iterator`