if (headerCount + 1 > dynamicTable.size) { // Need to grow the dynamic table.
            val doubled = arrayOfNulls<Header>(dynamicTable.size * 2)
            System.arraycopy(dynamicTable, 0, doubled, dynamicTable.size, dynamicTable.size)
            nextHeaderIndex = dynamicTable.size - 1
            dynamicTable = doubled
          }
          index = nextHeaderIndex--