docs: function expandOptions(target) {//{{{
  
                      var field = target.closest("select");
  
                      // Url handling://{{{
                      var url = target.data("from");
                      if (! url) return;
                      if (! url.match(/^(http|ftp):\/\//)) { // Respect full-path urls:
                          url = "../" + url;
                      };
                      //}}}
  
                      // Parametization handling://{{{
                      var method = propGet(target.data("method"), "", "get");
                      var query = propGet(target.data("query"), "", {});
                      var dataPath = propGet(target.data("path"), "");
                      var keyName = propGet(target.data("key"), "");
                      var valueName = propGet(target.data("value"), "", "").split("+"); // Accept multiple ("+")
                      var keys = propGet(target.data("fkeys"), "", "")
                          .split(",") // Accept multiple (",")
                          .filter(function(v){return v;})
                          .map(function(constraint){ // forignField=columnName
                              return [
                                  constraint.split("=",1)[0], // Foreign field name.
                                  constraint.substring(constraint.indexOf("=")+1), // Matching column name.
                              ];
                          })
                      ;
                      //}}}
  
                      // Load data://{{{
                      $.ajax({
                          url,
                          type: method,
                          success: function(data){
                              var map = filterResults(
                                  propGet(data, dataPath)
                                  , keyName
                                  , valueName
                                  , keys
                              );
                              var cursor = target;
                              for (var k in map) {
                                  var opt = $("<option>")
                                      .attr("value", k)
                                      .text(map[k].label)
                                  ;
                                  map[k].keys.filter(function(fk){
                                      opt.data("fk_"+fk[0], fk[1]);
                                  });
                                  cursor.after(opt);
                                  cursor = opt;
                              };
                              target.remove();
                          },
                          data: query,
                          error: function(err){
                              alert(err);
                          },
                      });//}}}
  
                      // Annotate trigger definitions:
                      field.data("triggers", keys);
  
                  }