xeus cling

Jupyter kernel for the C++ programming language



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xeus-cling is a Jupyter kernel for C++ based on the C++ interpreter cling and
the native implementation of the Jupyter protocol xeus.


xeus-cling has been packaged for the mamba (or conda) package manager on the Linux and OS X platforms. At the moment, we are not providing packages for the Windows platform.

To ensure that the installation works, it is preferable to install xeus-cling in a fresh environment. It is also needed to use a miniforge or miniconda installation because with the full anaconda you may have a conflict with the ZeroMQ library which is already installed in the anaconda distribution.

Installation with mamba or conda

The safest usage is to create an environment named cling:

mamba create -n cling
source activate cling

Then you can install in this environment xeus-cling and its dependencies

mamba install xeus-cling -c conda-forge

Installation from source

You will first need to create a new environment and install the dependencies:

mamba create -n xeus-cling -c conda-forge cmake xeus-zmq cling nlohmann_json=3.11.2 cppzmq xtl pugixml doctest cpp-argparse
source activate xeus-cling

Please refer to environment-host.yml for packages specific versions to install if applicable.

You can then compile the sources. From the build directory, run:

make && make install

If you don’t have a frontend already installed (classic Jupyter Notebook or JupyterLab for instance), install one:

mamba install jupyterlab -c conda-forge

Trying it online

To try out xeus-cling interactively in your web browser, just click on the binder



To get started with using xeus-cling, check out the full documentation



Launch the jupyter notebook with jupyter notebook and launch a new C++ notebook by selecting the C++17 kernel in the new dropdown.

A C++ notebook

You can now make use of the C++ programming language in the Jupyter notebook.

A C++ notebook

Inline help and tab-completion

Quick help is shown on the pager with the special ? magic.


Content for the quick help is available for the standard library, and can be made available for third-party packages.

Rendering of rich outputs

Rich output

Jupyter interactive widgets

A C++ backend for the Jupyter interactive widgets is available in the xwidgets package.



xeus-cling depends on

xeus-cling xeus-zmq xtl cling pugixml cppzmq cpp-argparse nlohmann_json dirent (windows only)
main >=1.1.0,<2.0.0 >=0.7.0,<0.8.0 >=0.9,<0.10 ~1.8.1 ~4.3.0 ~3.0 ~3.11.2 >=2.3.2,❤️
0.15.3 >=1.1.0,<2.0.0 >=0.7.0,<0.8.0 >=0.9,<0.10 ~1.8.1 ~4.3.0 ~2.9 >=3.6.1,<4.0 >=2.3.2,❤️
0.15.2 >=1.1.0,<2.0.0 >=0.7.0,<0.8.0 >=0.9,<0.10 ~1.8.1 ~4.3.0 ~2.9 >=3.6.1,<4.0 >=2.3.2,❤️
0.15.1 >=1.0.0,<2.0.0 >=0.7.0,<0.8.0 >=0.9,<0.10 ~1.8.1 ~4.3.0 ~2.9 >=3.6.1,<4.0 >=2.3.2,❤️
0.15.0 >=1.0.0,<2.0.0 >=0.7.0,<0.8.0 >=0.9,<0.10 ~1.8.1 ~4.3.0 ~2.9 >=3.6.1,<4.0 >=2.3.2,❤️

Prior to version 0.15, xeus-cling was depending on cxxopts instead of cpp-argparse.

xeus-cling xeus-zmq xtl cling pugixml cppzmq cxxopts nlohmann_json dirent (windows only)
0.14.0 >=1.0.0,<2.0.0 >=0.7.0,<0.8.0 >=0.6,<0.9 ~1.8.1 ~4.3.0 >=2.1.1,<=2.2 >=3.6.1,<4.0 >=2.3.2,❤️

Prior to version 0.14, xeus-cling was depending on xeus instead of xeus-zmq:

xeus-cling xeus xtl cling pugixml cppzmq cxxopts nlohmann_json dirent (windows only)
0.13.0 >=2.0.0,❤️.0.0 >=0.7.0,<0.8.0 >=0.6,<0.9 ~1.8.1 ~4.3.0 >=2.1.1,<=2.2 >=3.6.1,❤️.10 >=2.3.2,❤️
0.12.1 >=1.0.0,<2.0.0 >=0.7.0,<0.8.0 >=0.6,<0.9 ~1.8.1 ~4.3.0 >=2.1.1,<=2.2 >=3.6.1,<4.0 >=2.3.2,❤️
0.12.0 >=1.0.0,<2.0.0 >=0.7.0,<0.8.0 >=0.6,<0.9 ~1.8.1 ~4.3.0 >=2.1.1,<=2.2 >=3.6.1,<4.0 >=2.3.2,❤️

xeus-cling requires its dependencies to be built with the same compiler and same C runtime as the one used to build cling.


See CONTRIBUTING.md to know how to contribute and set up a development environment.


We use a shared copyright model that enables all contributors to maintain the
copyright on their contributions.

This software is licensed under the BSD-3-Clause license. See the LICENSE file for details.