feat: add library description

ffg/README.md

@@ -0,0 +1,51 @@
+# fusion-function-generator (ffg)
+
+![CI](https://github.com/nicdard/fusion-function-generator/actions/workflows/ci.yml/badge.svg)
+
+Automatic generation of [Fusion Functions](https://yinyang.readthedocs.io/en/latest/fusion.html#fusion-functions) 
+used by 
+[yinyang](https://yinyang.readthedocs.io/en/latest/index.html) fuzzer for [Semantic Fusion](https://yinyang.readthedocs.io/en/latest/fusion.html).
+
+## Lib structure
+
+The package is divided into 4 folders:
+* gen
+* operators
+* visitors
+* emitter
+
+The folder `gen` contains the code which is used to generate the whole
+`operators` folder, the [configuration file](ffg/gen/gen_configuration.py) exposing some api to control which operators to use during the generation of the tree as well as some constants for the options to the generation algorithm.
+the file `tree_generation` instead contains the main tree generation algorithm.
+
+`operators` contains the basic definition of the operators classes.
+
+`visitors` folder contains useful api to print, export to DOT format and rewrite the trees to their inverses.
+
+Finally, `emitter` includes the code needed to export fusion functions to the format understood by YinYang. It also contains an emitter that outputs fusion functions and its inverses to DOT file.
+
+## Cookbook
+
+Use only a subset of the theories in the generation:
+```python
+ffg.gen.gen_configuration.set_available_theories(['bool', 'real'])
+```
+
+Get the available theories:
+```python
+ffg.gen.gen_configuration.get_theories()
+```
+
+Generate a fusion function of two vairables (as a tree):
+```python
+tree, _ = ffg.gen.tree_generation.generate_tree(root_type, size, ['x', 'y'], 'z')
+```
+
+Emit the fusion function to YinYang format as a string:
+```python
+output = io.StringIO()
+emit_function(tree, output, is_wrapped=False)
+ff = output.getvalue()
+```
+
+

setup.py

@@ -24,7 +24,7 @@
 from setuptools import find_packages, setup
 
 this_directory = Path(__file__).parent
-long_description = (this_directory / "README.md").read_text()
+long_description = (this_directory / "ffg/README.md").read_text()
 
 setup(
     name='ffg',