Problem: Cannot get a list of positions describing a region
(Justin M. Keyes, after v9.1.0120)
Solution: Add the getregionpos() function
(Shougo Matsushita)
fixes: vim/vim#14609closes: vim/vim#14617b4757e627e
Co-authored-by: Shougo Matsushita <Shougo.Matsu@gmail.com>
Co-authored-by: Justin M. Keyes <justinkz@gmail.com>