NAME¶

get_subcommand(3f) - [ARGUMENTS:M_CLI2] special-case routine for handling subcommands on a command line (LICENSE:PD)

SYNOPSIS¶

function get_subcommand()

    character(len=:),allocatable :: get_subcommand

DESCRIPTION¶

In the special case when creating a program with subcommands it is assumed the first word on the command line is the subcommand. A routine is required to handle response file processing, therefore this routine (optionally processing response files) returns that first word as the subcommand name.

It should not be used by programs not building a more elaborate command with subcommands.

RETURNS¶

NAME

name of subcommand

EXAMPLE¶

Sample program:

   program demo_get_subcommand


   !x! SUBCOMMANDS


   !x! For a command with subcommands like git(1)


   !x! you can make separate namelists for each subcommand.


   !x! You can call this program which has two subcommands (run, test),


   !x! like this:


   !x!    demo_get_subcommand --help


   !x!    demo_get_subcommand run -x -y -z --title -l -L


   !x!    demo_get_subcommand test --title -l -L --testname


   !x!    demo_get_subcommand run --help


      implicit none


   !x! DEFINE VALUES TO USE AS ARGUMENTS WITH INITIAL VALUES


      real               :: x=-999.0,y=-999.0,z=-999.0


      character(len=80)  :: title="not set"


      logical            :: l=.false.


      logical            :: l_=.false.


      character(len=80)  :: testname="not set"


      character(len=20)  :: name


      call parse(name) !x! DEFINE AND PARSE COMMAND LINE


      !x! ALL DONE CRACKING THE COMMAND LINE.


      !x! USE THE VALUES IN YOUR PROGRAM.


      write(*,*)'command was ',name


      write(*,*)'x,y,z .... ',x,y,z


      write(*,*)'title .... ',title


      write(*,*)'l,l_ ..... ',l,l_


      write(*,*)'testname . ',testname


   contains


   subroutine parse(name)


   !x! PUT EVERYTHING TO DO WITH COMMAND PARSING HERE FOR CLARITY


   use M_CLI2, only : set_args, get_args, get_args_fixed_length


   use M_CLI2, only : get_subcommand, set_mode


   character(len=*)              :: name    ! the subcommand name


   character(len=:),allocatable  :: help_text(:), version_text(:)


      call set_mode('response_file')


   ! define version text


      version_text=[character(len=80) :: &


         '@(#)PROGRAM:     demo_get_subcommand            >', &


         '@(#)DESCRIPTION: My demo program  >', &


         '@(#)VERSION:     1.0 20200715     >', &


         '@(#)AUTHOR:      me, myself, and I>', &


         '@(#)LICENSE:     Public Domain    >', &


         '' ]


       ! general help for "demo_get_subcommand --help"


       help_text=[character(len=80) :: &


        ' allowed subcommands are          ', &


        '   * run  -l -L --title -x -y -z  ', &


        '   * test -l -L --title           ', &


        '' ]


      ! find the subcommand name by looking for first word on command


      ! not starting with dash


      name = get_subcommand()


      select case(name)


      case('run')


       help_text=[character(len=80) :: &


        '                                  ', &


        ' Help for subcommand "run"        ', &


        '                                  ', &


        '' ]


       call set_args( &


       & '-x 1 -y 2 -z 3 --title "my title" -l F -L F',&


       & help_text,version_text)


       call get_args('x',x)


       call get_args('y',y)


       call get_args('z',z)


       call get_args_fixed_length('title',title)


       call get_args('l',l)


       call get_args('L',l_)


      case('test')


       help_text=[character(len=80) :: &


        '                                  ', &


        ' Help for subcommand "test"       ', &


        '                                  ', &


        '' ]


       call set_args(&


       & '--title "my title" -l F -L F --testname "Test"',&


       & help_text,version_text)


       call get_args_fixed_length('title',title)


       call get_args('l',l)


       call get_args('L',l_)


       call get_args_fixed_length('testname',testname)


      case default


       ! process help and version


       call set_args(' ',help_text,version_text)


       write(*,'(*(a))')'unknown or missing subcommand [',trim(name),']'


       write(*,'(a)')[character(len=80) ::  &


       ' allowed subcommands are          ', &


       '   * run  -l -L -title -x -y -z   ', &


       '   * test -l -L -title            ', &


       '' ]


       stop


      end select


   end subroutine parse


   end program demo_get_subcommand

AUTHOR¶

John S. Urban, 2019

LICENSE¶

Public Domain