Function useNextSlot

src/codemirror.js:9821–9828

(cursor)

        var current = pointer % size;
        var curMark = buffer[current];
        function useNextSlot(cursor) {
          var next = ++pointer % size;
          var trashMark = buffer[next];
          if (trashMark) {
            trashMark.clear();
          }
          buffer[next] = cm.setBookmark(cursor);
        }
        if (curMark) {
          var markPos = curMark.find();
          // avoid recording redundant cursor position