is_fortran_name Function

elemental function is_fortran_name(line) result (lout)
! determine if a string is a valid Fortran name ignoring trailing spaces
! (but not leading spaces)
    character(len=*),parameter   :: int='0123456789'
    character(len=*),parameter   :: lower='abcdefghijklmnopqrstuvwxyz'
    character(len=*),parameter   :: upper='ABCDEFGHIJKLMNOPQRSTUVWXYZ'
    character(len=*),parameter   :: allowed=upper//lower//int//'_'
    character(len=*),intent(in)  :: line
    character(len=:),allocatable :: name
    logical                      :: lout
        name=trim(line)
        if(len(name)/=0)then
            lout = .true.                                  &
             & .and. verify(name(1:1), lower//upper) == 0  &
             & .and. verify(name,allowed) == 0             &
             & .and. len(name) <= 63
        else
            lout = .false.
        endif
end function is_fortran_name