Skip to main content

Annotate AST trees with source code positions

Project description

The asttokens module annotates Python abstract syntax trees (ASTs) with the positions of tokens and text in the source code that generated them.

It makes it possible for tools that work with logical AST nodes to find the particular text that resulted in those nodes, for example for automated refactoring or highlighting.

Installation

asttokens is available on PyPI: https://pypi-hypernode.com/pypi/asttokens/:

pip install asttokens

The code is available on GitHub: https://github.com/gristlabs/asttokens.

Usage

asttokens work with both Python2 and Python3. Here’s an example:

import asttokens, ast
source = "Robot('blue').walk(steps=10*n)"
atok = asttokens.ASTTokens(source)
tree = ast.parse(source)
atok.mark_tokens(tree)

Once the tree has been marked, nodes get .first_token, .last_token attributes, and the ASTTokens object offers helpful methods:

attr_node = next(n for n in ast.walk(tree) if isinstance(n, ast.Attribute), None)
print(atok.get_text(attr_node))
start, end = attr_node.last_token.startpos, attr_node.last_token.endpos
print(atok.text[:start] + 'RUN' + atok.text[end:])

Which produces this output:

Robot('blue').walk
Robot('blue').RUN(steps=10*n)

The ASTTokens object also offers methods to walk and search the list of tokens that make up the code (or a particular AST node), which is more useful and powerful than dealing with the text directly.

Tests

Tests are in the tests/ subdirectory. To run all tests, run:

nosetests

Project details


Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

asttokens-1.0.0.tar.gz (27.7 kB view details)

Uploaded Source

Built Distribution

asttokens-1.0.0-py2.py3-none-any.whl (18.0 kB view details)

Uploaded Python 2 Python 3

File details

Details for the file asttokens-1.0.0.tar.gz.

File metadata

  • Download URL: asttokens-1.0.0.tar.gz
  • Upload date:
  • Size: 27.7 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No

File hashes

Hashes for asttokens-1.0.0.tar.gz
Algorithm Hash digest
SHA256 f53b378b9f036f1f574fb8acda0dd8530ec31362803d0326908169af04e6b271
MD5 70726251cfa6d0c5be4db16d8f2f5c7c
BLAKE2b-256 07ae0e23b26fc8325305820238f45bb0a6ea6b494c326342a29e7ee33d061428

See more details on using hashes here.

File details

Details for the file asttokens-1.0.0-py2.py3-none-any.whl.

File metadata

File hashes

Hashes for asttokens-1.0.0-py2.py3-none-any.whl
Algorithm Hash digest
SHA256 80963b9a813e43616b2405e3cb3627c586a5d5e3d1f01282e46e9f3a148d7b26
MD5 06206630a0d32d29d1aceeb62c6eb1d4
BLAKE2b-256 5ee48a37f65bcbcd56ad0508dbf48ee6b368d6b8daaef83dfde76e728b1a8f00

See more details on using hashes here.

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page