---
title: External importer example
python: https://github.com/rerun-io/rerun/tree/latest/examples/python/external_importer/rerun-importer-python-file.py
rust: https://github.com/rerun-io/rerun/tree/latest/examples/rust/external_importer/src/main.rs
cpp: https://github.com/rerun-io/rerun/tree/latest/examples/cpp/external_importer/main.cpp
thumbnail: https://static.rerun.io/external_data_loader_cpp/83cd3c2a322911cf597cf74aeda01c8fe83e275f/480w.png
---

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This is an example executable importer plugin for the Rerun Viewer.

It will log C++ source code files as markdown documents.
To try it out, compile it and place it in your $PATH, then open a C++ source file with Rerun (`rerun file.cpp`).

Consider using the [`send_columns`](https://ref.rerun.io/docs/cpp/stable/classrerun_1_1RecordingStream.html#ad17571d51185ce2fc2fc2f5c3070ad65) API for importers that ingest time series data from a file.
This can be much more efficient that the stateful `log` API as it allows bundling
component data over time into a single call consuming a continuous block of memory.