demo2.f90

program demo2
!! FULL EXAMPLE ADDING HELP AND VERSION DISPLAY
   use M_CLI,  only : unnamed
   implicit none
   integer            :: i

!! DEFINE VALUES TO PUT IN NAMELIST "ARGS"
   real               :: x        
   real               :: y
   real               :: z
   real               :: point(3)
   character(len=80)  :: title
   logical            :: l
   logical            :: l_

   call parse() !! DEFINE AND PARSE COMMAND LINE

   !! ALL DONE CRACKING THE COMMAND LINE USE THE VALUES IN YOUR PROGRAM.
   write(*,*)x+y+z
   write(*,*)point*2
   write(*,*)title
   write(*,*)l,l_

   !! THE OPTIONAL UNNAMED VALUES ON THE COMMAND LINE ARE
   !! ACCUMULATED IN THE CHARACTER ARRAY "UNNAMED"
   if(size(unnamed).gt.0)then
      write(*,'(a)')'files:'
      write(*,'(i6.6,3a)')(i,'[',unnamed(i),']',i=1,size(unnamed))
   endif

contains
   subroutine parse()
   !! PUT EVERYTHING TO DO WITH COMMAND PARSING HERE FOR CLARITY
   use M_CLI, only : commandline, check_commandline
   character(len=255)            :: message ! use for I/O error messages
   character(len=:),allocatable  :: readme ! stores updated namelist
   character(len=:),allocatable  :: help_text(:), version_text(:)
   integer                       :: ios

   !! DEFINE COMMAND PROTOTYPE
   !!  o All parameters must be listed with a default value
   !!  o string values  must be double-quoted
   !!  o numeric lists must be comma-delimited. No spaces are allowed
   !!  o a short uppercase name -L maps to a variable in the NAMELIST of name L_
   !!  o long keynames must be all lowercase

   namelist/args/x,y,z,point,title,l,l_
   character(len=*),parameter :: cmd='&
   & -x 1 -y 2 -z 3     &
   & --point -1,-2,-3   &
   & --title "my title" &
   & -l F -L F          &
   & '

      help_text=[character(len=80) :: &
         'NAME                                                    ', &
         '   myprocedure(1) - make all things possible            ', &
         'SYNOPSIS                                                ', &
         '   function myprocedure(stuff)                          ', &
         '   class(*) :: stuff                                    ', &
         'DESCRIPTION                                             ', &
         '   myprocedure(1) makes all things possible given STUFF ', &
         'OPTIONS                                                 ', &
         '   STUFF  things to do things to                        ', &
         'RETURNS                                                 ', &
         '   MYPROCEDURE  the answers you want                    ', &
         'EXAMPLE                                                 ', &
         '' ]

      version_text=[character(len=80) :: &
         '@(#)PROGRAM:     demo2            >', &
         '@(#)DESCRIPTION: My demo program  >', &
         '@(#)VERSION:     1.0 20200115     >', &
         '@(#)AUTHOR:      me, myself, and I>', &
         '@(#)LICENSE:     Public Domain    >', &
         '' ]

      readme=commandline(cmd)
      read(readme,nml=args,iostat=ios,iomsg=message)
      call check_commandline(ios,message,help_text,version_text)

   end subroutine parse

end program demo2