公共接口运算符(==)
如果set1和set2中的所有位都具有相同的值，则返回.true.，否则返回.false.。集合必须具有相同数量的位，否则结果未定义。（规范）
示例
program example_equality
use stdlib_bitsets
type(bitset_64) :: set0, set1, set2
call set0 % init( 33 )
call set1 % init( 33 )
call set2 % init( 33 )
call set1 % set( 0 )
call set2 % set( 32 )
if ( set0 == set0 .and. set1 == set1 .and. set2 == set2 .and. &
.not. set0 == set1 .and. .not. set0 == set2 .and. .not. &
set1 == set2 ) then
write(*,*) 'Passed 64 bit equality tests.'
else
error stop 'Failed 64 bit equality tests.'
end if
end program example_equality