attempt for universal way of opening a filetype with default application (regardless of windowmanager)

launch.bash

#!/bin/bash
# attempt for universal way of opening a filetype with default application (regardless of windowmanager)
# usage: open my.pdf   (HINT: put this in your .bashrc: alias o='launch' )
# @param string (arguments)

function launch(){
  if   which xdg-open   &>/dev/null;
    then xdg-open "$@"
  elif which gnome-open &>/dev/null;
    then gnome-open "$@";
  elif which kde-open   &>/dev/null;
    then kde-open "$@";
  elif which open       &>/dev/null; 
    then open "$@"
  fi
}