ADL (a)

Continued from Argument Dependent Lookup (ADL).

To suppress ADL, we surround the function call in parenthesis. Consider the following example.

namespace my {
template <typename RandomIt>
void sort(RandomIt begin, RandomIt end) {
	// Doing a merge sort, then call sort recursively
	sort(begin, mid);
}
}

The recursive call to sort is ambiguous when a vector’s iterators are given as ADL also gives std::sort. To fix it, change the call to (sort)(begin, mid). This suppresses ADL.