text: function sha1_file (str_filename) {
    // From: http://phpjs.org/functions
    // +   original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
    // -    depends on: file_get_contents
    // -    depends on: sha1
    // *     example 1: sha1_file('http://kevin.vanzonneveld.net/pj_test_supportfile_1.htm');
    // *     returns 1: '40bd001563085fc35165329ea1ff5c5ecbdbbeef'
    var buf = this.file_get_contents(str_filename);
    return this.sha1(buf);
  }
  