Apache License
                           Version 2.0, January 2004
                        http://www.apache.org/licenses/

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

   ----------------------------------------------------------------------

   This project is a MoonBit port inspired by HuggingFace `tokenizers`
   (https://github.com/huggingface/tokenizers), which is licensed under
   the Apache License 2.0. Algorithms (BPE, byte-level BPE, WordPiece,
   Unigram) and the tokenizer.json format follow that project.