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README.md

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+# 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](https://github.com/google/python-fire).
+
+## Basic example
+
+Given the following source file `calc.cc`:
+
+```c++
+#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 [Installation](#installation).
+Alternatively, if you're building `calc` with CMake you could use the
+`fire_llvm_config` function:
+
+```cmake
+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 12.0.\*, minor tweaks might be needed for other
+versions.
+
+To build the plugin, run:
+
+```
+mkdir build
+cd build
+cmake ..
+make
+```
+
+which will create the plugin under
+`build/fire-llvm/plugin/libfire-llvm-plugin.so`.
+
 ## Ackknowledgements
 
 fire-llvm is based on [fire-hpp](https://github.com/kongaskristjan/fire-hpp).