beman.execution

beman.execution: Building Block For Asynchronous Programs

Library Status Standard Target Coverage

beman.execution provides the basic vocabulary for asynchronous programming as well as important algorithms implemented in terms of this vocabulary. The key entities of the vocabulary are:

  • scheduler used to control where operations are executed.

    • The key operation is schedule(scheduler) → sender.

  • sender used to represent work.

    • The key operation is connect(sender, receiver) → operation-state.

  • receiver used to receive completion notifications.

    • There are multiple operations on receivers:

      • set_value(receiver, args…​) for successful completions.

      • set_error(receiver, error) to report errors.

      • set_stopped(receiver) to report cancellation.

  • operation-state to represent a ready to run work graph .

    • The key operation is start(state).

Using these operations some fundamental algorithms are implemented, e.g.:

  • just(args…​) as the starting point of a work graph without a specified scheduler`.

  • let_value(sender, fun) to produce a sender based on `sender’s results.

  • on(scheduler, sender) to execute sender on scheduler.

  • transfer(sender, scheduler) to complete with with sender’s results on `scheduler.

  • when_all(sender …​) to complete when all `sender`s have completed.

  • bulk(…​) to executed execute work, potentially concurrently.

Implements: std::execution (P2300R10).

Status: Under development and not yet ready for production use.

Help Welcome!

There are plenty of things which need to be done. See the contributions page for some ideas how to contribute. The resources page contains some links for general information about the sender/receivers and std::execution.

Build

Preconditions

  • cmake v3.30 or newer

  • ninja v1.13.0 or newer

  • A compiler that supports at least C++23

Library Linux MacOS Windows

build

Linux build status

MacOS build status

Window build status

The following instructions build the library and the examples:

ln -s cmake/CMakeUserPresets.json .
cmake --workflow --list-presets
Available workflow presets:

  "debug"
  "release"
  "gcc-debug"
  "gcc-release"
  "llvm-debug"
  "llvm-release"
  "msvc-debug"
  "msvc-release"


CXX=g++-15 cmake --workflow --preset release

The implementation compiles and passes tests using clang, gcc, and MSVC++.

Supported Platforms

Compiler Version C++ Standards Standard Library

GCC

15-14

C26, C23

libstdc++

Clang

22-19

C26, C23

libc++

MSVC

latest

C++23

MSVC STL

License

beman.execution is licensed under the Apache License v2.0 with LLVM Exceptions.

Examples