Convert Python Abstract Syntax Trees (ASTs) to readable source code.
Xylem is useful for when you want to make dynamic changes to Python code/ASTs, but also need to write those changes back as source code.
It's also very small (<500 lines), pure-Python, and produces (mostly) readable source code.
In writing this, I made heavy use of the unofficial AST documentation at Green Tree Snakes.
Xylem will work on Python 3.4 or later. I'll eventually get around to testing it on Python 2.7-3.3.
Install Xylem by running pip3 install xylem from the command line.
Note
On some Linux systems, installation may require running pip with root permissions, or running pip3 install xylem --user. The latter may require exporting ~/.local/bin to PATH.
Clone or download the git repo, navigate to the directory, and run:
python3 setup.py sdist cd dist pip3 install xylem-<version>.tar.gz
to_source is likely the only method you'll need to use:
>>> from xylem import to_source
>>> import ast
>>> tree = ast.parse("print('hello world')")
>>> ast.dump(tree)
"Module(body=[Expr(value=Call(func=Name(id='print', ctx=Load()), args=[Str(s='Hello world')], keywords=[]))])"
>>> to_source(tree)
"print('hello world')"compare_ast may also be useful for determining if two ASTs are functionally equivalent.
Xylem versioning functions on a MAJOR.MINOR.PATCH.[DEVELOP] model. Only stable, non development releases will be published to PyPI. Because Xylem is still a beta project, the MAJOR increment will be 0. Minor increments represent new features. Patch increments represent problems fixed with existing features.