#+begin_src cfengine3
bundle agent __main__
{
  files:

      "/tmp/example-edit.filename.txt" content => "Hello World!";

      "/tmp/example-edit.filename.txt"
        edit_line => show_edit_filename;

}

bundle edit_line show_edit_filename
{
  reports:
      "$(with)"
        with => concat( "I found the string 'World' in the file being ",
                        "edited ('$(edit.filename)')"),
        if => strcmp( "false", "$(edit.empty_before_use)"); # It's probably
      # useless to probe
      # the content of the
      # file if you are
      # ignoring
      # pre-existing
      # content.

      "$(with)"
        with => concat( "It's probably not very useful to inspect content",
                        "that is being thrown away." ),
        if => strcmp( "true", "$(edit.empty_before_use)");

      "$(with)"
        with => concat ( "This version of CFEngine does not know if the",
                         "edit operation is expected to ignore pre-existing ",
                         "content the variable 'edit.empty_before_use' does ",
                         "not exist"),
        unless => isvariable ( "edit.empty_before_use" );

}

body edit_defaults my_empty_file_before_editing
{
        empty_file_before_editing => "true"; # The variable
                                             # edit.empty_before_use allows this
                                             # to be known from within an
                                             # edit_line bundle.
}
#+end_src
###############################################################################
#+begin_src example_output
#@ ```
#@ R: I found the string 'World' in the file being edited ('/tmp/example-edit.filename.txt')
#@ ```
#+end_src