Can You Remove Elements from a Vector During a C 11 Range-based For Loop?

Managing Vector Elements within Range-based for Loops

In C 11, range-based for loops provide a convenient way to iterate over the elements of a container. However, certain operations, such as removing elements from a vector, become problematic within these loops.

Can Elements be Removed from a Vector during C 11 Range-based for Loops?

Unfortunately, no. Range-based for loops are designed for one-time iteration of each element in a container. They are not suitable for modifying the container itself, including removing elements.

Alternative for Element Removal:

To remove elements from a vector within a loop, you must use the traditional for loop or its variants. These allow for modifications and non-linear traversal of the container.

Example:

auto i = std::begin(inv);

while (i != std::end(inv)) {
    // Do some stuff
    if (blah)
        i = inv.erase(i);
    else
        ++i;
}

By using the std::begin and std::end functions, the loop iterates over the vector using iterators. When an element is marked for removal, the erase function is called, which invalidates the iterator pointing to the removed element. The loop then continues by advancing the iterator.

In conclusion, while range-based for loops offer ease of use for read-only iteration, for operations like removing elements from vectors, you need to employ traditional for loops to maintain control over container modification.

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