program volatile_doctest use stringifor_string_t type(string) :: string1 logical :: test_passed(2) string1 = 'ell' test_passed(1) = verify(s='Hello World Hello!', set=string1)==verify(string='Hello World Hello!', set='llo') test_passed(2) = verify(s='Hello World Hello!', set=string1, back=.true.)==verify(string='Hello World Hello!', set='llo', & back=.true.) print '(L1)', all(test_passed) endprogram volatile_doctest