class Optimist::IOOption

in the case of file-paths given to it.
Note that this will return the file-handle, not the file-name
Option class for handling IO objects and URLs.

def parse(paramlist, _neg_given) 

def parse(paramlist, _neg_given)
  paramlist.map do |pg|
    pg.map do |param|
      if param =~ /^(stdin|-)$/i
        $stdin
      else
        require 'open-uri'
        begin
          open param
        rescue SystemCallError => e
          raise CommandlineError, "file or url for option '#{self.name}' cannot be opened: #{e.message}"
        end
      end
    end
  end
end

def type_format ; "=<filename/uri>" ; end 

def type_format ; "=<filename/uri>" ; end