Carbon
A dark-gray circle with a white sans-serif letter "C" in the middle
Logo on Carbon's GitHub organization
FamilyC
Designed byGoogle
Typing disciplineStatic, nominative, partly inferred
Implementation languageC++
LicenseApache-2.0-with-LLVM-Exception
Filename extensions.carbon
Websitegithub.com/carbon-language
Influenced by
C++, Rust, Swift[citation needed]

Carbon is an experimental programming language designed for interoperability with C++.[1] The project is open-source and was started at Google. Google engineer Chandler Carruth first introduced Carbon at the CppNorth conference in Toronto in July 2022. He stated that Carbon was created to be a C++ successor.[2][3][4] The language is expected to have an experimental MVP version 0.1 in 2025 and a production-ready version 1.0 after 2027.[5]

The language intends to fix several perceived shortcomings of C++[6] but otherwise provides a similar feature set. The main goals of the language are readability and "bi-directional interoperability" (which allows the user to include C++ code in the Carbon file), as opposed to using a new language like Rust, that, while being influenced by C++, is not two-way compatible with C++ programs. Changes to the language will be decided by the Carbon leads.[7][8][9][10]

Carbon's documents, design, implementation, and related tools are hosted on GitHub under the Apache-2.0 license with LLVM Exceptions.[11]

Example

The following shows how a program might be written in Carbon and C++:[12]

Carbon C++
package Geometry api;
import Math;

class Circle {
  var r: f32;
}

fn PrintTotalArea(circles: Slice(Circle)) {
  var area: f32 = 0;
  for (c: Circle in circles) {
    area += Math.Pi * c.r * c.r;
  }
  Print("Total area: {0}", area);
}

fn Main() -> i32 {
  // A dynamically sized array, like `std::vector`.
  var circles: Array(Circle) = ({.r = 1.0}, {.r = 2.0});
  // Implicitly converts `Array` to `Slice`.
  PrintTotalArea(circles);
  return 0;
}
#include <math.h>
#include <iostream>
#include <span>
#include <vector>

struct Circle {
  float r;
};

void PrintTotalArea(std::span<Circle> circles) {
  float area = 0;
  for (const Circle& c : circles) {
    area += M_PI * c.r * c.r;
  }
  std::cout << "Total area: " << area << "\n";
}

auto main(int argc, char** argv) -> int {
  std::vector<Circle> circles = ((1.0}, {2.0));
  // Implicitly converts `vector` to `span`.
  PrintTotalArea(circles);
  return 0;
}

See also

References

  1. ^ "README". Retrieved 6 September 2023. It is designed around interoperability with C++ as well as large-scale adoption and migration for existing C++ codebases and developers.
  2. ^ "Scheduled events for Tuesday, July 19, 09:00 - 10:30". CppNorth, The Canadian C++ Conference, July 17–20, 2022. CppNorth. Retrieved 21 July 2022 – via Sched.com.
  3. ^ "Carbon Language: An experimental successor to C++ - Chandler Carruth - CppNorth 2022". CppNorth. 22 July 2022 – via YouTube.
  4. ^ Bradshaw, Kyle (19 July 2022). "Carbon, a new programming language from Google, aims to be C++ successor". 9to5Google.
  5. ^ Carbon Language: Roadmap, carbon-language, 11 January 2024, retrieved 18 January 2024
  6. ^ "Difficulties improving C++". carbon-language/carbon-lang repo. Google. 21 July 2022 – via GitHub.
  7. ^ Carruth, Chandler; Ross-Perkins, Jon; Riley, Matthew; Hummert, Sidney (23 July 2022). "Evolution and governance". carbon-language/carbon-lang repo. Google – via GitHub.
  8. ^ Illidge, Myles (21 July 2022). "Google's Carbon programming language aims to replace C++". MyBroadband.
  9. ^ Jackson, Joab (20 July 2022). "Google Launches Carbon, an Experimental Replacement for C++". The New Stack.
  10. ^ Mustafa, Onsa (20 July 2022). "Carbon, A New Programming Language from Google As A C++ Successor". PhoneWorld.
  11. ^ "carbon-lang/LICENSE". GitHub. 16 June 2020. Retrieved 24 July 2022.
  12. ^ "carbon-lang/docs/images/snippets.md at trunk · carbon-language/carbon-lang". GitHub. Retrieved 16 December 2023.