fire-llvm

fire-llvm is a Clang plugin that can be used to turn ordinary C++ functions and objects into command line interfaces (CLIs) similarly to python-fire.

Basic example

Given the following source file calc.cc:

#include <fire-llvm/fire.hpp>

struct Calculator
{
  int add(int a, int b)
  {
    return a + b;
  }

  int sub(int a, int b)
  {
    return a - b;
  }
};

Calculator calc;

int main()
{
  fire::fire_llvm(calc);
}

run clang++ -Xclang -load -Xclang $FIRE_LLVM_PLUGIN -Xclang -add-plugin -Xclang fire -I fire-llvm/include calc.cc -o calc to create an executable calc. Here, $FIRE_LLVM_PLUGIN should expand to the location of the shared object created when building this plugin (see Installation). Alternatively, if you're building calc with CMake you could use the fire_llvm_config function:

add_executable(calc calc.cc)
fire_llvm_config(calc)

You can then use calc as follows:

$> ./calc add -a=1 -b=2
3
$> ./calc sub -a=1 -b=2
-1

For more examples, take a look at the tests in the tests directory.

Installation

To build fire-llvm you will need the LLVM development libraries. I have tested this with Clang/LLVM version 11 and 12. Minor tweaks might be needed for other versions.

To build the plugin, run:

mkdir build
cd build
cmake .. -DCMAKE_CXX_COMPILER=clang++
make

where clang++ should have version 11 or 12. This will create the plugin under build/fire-llvm/plugin/libfire-llvm-plugin.so. Due to some CMake wonkiness the build will likely fail if you try to run several make jobs in parallel with -j.

Ackknowledgements

fire-llvm is based on fire-hpp.