code: function (path, callback) {
              var that = this;
              this.queue.push(path);
  
              //
              // Import a file asynchronously
              //
              less.Parser.importer(path, this.paths, function (e, root) {
                  that.queue.splice(that.queue.indexOf(path), 1); // Remove the path from the queue
  
                  var imported = path in that.files;
  
                  that.files[path] = root;                        // Store the root
  
                  if (e && !that.error) { that.error = e }
  
                  callback(e, root, imported);
  
                  if (that.queue.length === 0) { finish(e) }       // Call `finish` if we're done importing
              }, env);
          }
docs: Error in parsing/evaluating an import