astor 0.1

Read/rewrite/write Python ASTs

astor is designed to allow easy manipulation of Python source via the AST.

There are some other similar libraries, but astor focuses on the following areas:

• Round-trip back to Python via Armin Ronacher’s codegen.py module:

  • Modified AST doesn’t need linenumbers, ctx, etc. or otherwise be directly compileable

  • Easy to read generated code as, well, code

• dump pretty-printing of AST

  • Harder to read than round-tripped code, but more accurate to figure out what is going on.

  • Easier to read than dump from built-in AST module

• Non-recursive treewalk

  • Sometimes you want a recursive treewalk (and astor supports that, starting at any node on the tree), but sometimes you don’t need to do that. astor doesn’t require you to explicitly visit sub-nodes unless you want to:

    • You can add code that executes before a node’s children are visited, and/or

    • You can add code that executes after a node’s children are visited, and/or

    • You can add code that executes and keeps the node’s children from being visited (and optionally visit them yourself via a recursive call)

  • Write functions to access the tree based on object names and/or attribute names

  • Enjoy easy access to parent node(s) for tree rewriting