C++23 Playground

A minimal C++23 project template using Bazel build system to explore and experiment with modern C++ features.

Features

• Zero Installation Compiler: Bazel automatically downloads LLVM 20.1.3 toolchain into its cache - no need to install a compiler on your system!
• Modern C++ Standards: Configured for C++23
• Hermetic Builds: Reproducible builds across different machines using the same cached toolchain
• Bazel Build System: Fast, incremental builds using Bzlmod
• Example Code: Demonstrates C++23 concepts with numeric type constraints

Prerequisites

• Bazel (latest version recommended)
• That's it! No compiler installation needed - Bazel handles everything

Quick Start

# Build the project (first run will download LLVM toolchain into Bazel cache)
bazel build //:main

# Run the executable
bazel run //:main

Note: On the first build, Bazel will download the LLVM 20.1.3 toolchain (~200MB) into its cache. This is a one-time operation. Subsequent builds will use the cached toolchain.

Project Structure

cpp23-playground/
├── BUILD.bazel          # Bazel build configuration
├── MODULE.bazel         # Bazel module definition
├── MODULE.bazel.lock    # Dependency lock file
├── .bazelrc             # Bazel configuration options
├── main.cpp             # Example C++23 code
└── README.md            # This file

What's Inside

The example code demonstrates:

• C++23 Concepts: Custom Numeric concept using type constraints
• Abbreviated Function Templates: Using auto parameters with concepts
• Modern Type Traits: std::integral and std::floating_point

Adding More Examples

To add new C++23 examples:

1. Create a new .cpp file
2. Add it to BUILD.bazel:

   cc_binary(
       name = "your_example",
       srcs = ["your_example.cpp"],
   )

3. Build and run: bazel run //:your_example

License

MIT License - feel free to use this as a template for your own C++23 projects.

Contributing

This is a personal playground, but suggestions for interesting C++23 examples are welcome!