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# Backrefs

Backrefs is a wrapper around Python's built-in [Re][re] and the 3rd party [Regex][regex] library.  Backrefs adds various
additional back references (and a couple other features) that are known to some regular expression engines, but not to
Python's Re and/or Regex.  The supported back references actually vary depending on the regular expression engine being
used as the engine may already have support for some.

```python
>>> from backrefs import bre
>>> pattern = bre.compile(r'(\p{Letter}+)')
>>> pattern.sub(r'\C\1\E', 'sometext')
'SOMETEXT'
```

# Documentation

https://facelessuser.github.io/backrefs/

# License

MIT

[github-ci-image]: https://github.com/facelessuser/backrefs/workflows/build/badge.svg
[github-ci-link]: https://github.com/facelessuser/backrefs/actions?query=workflow%3Abuild+branch%3Amaster
[codecov-image]: https://img.shields.io/codecov/c/github/facelessuser/backrefs/master.svg?logo=codecov&logoColor=aaaaaa&labelColor=333333
[codecov-link]: https://codecov.io/github/facelessuser/backrefs
[pypi-image]: https://img.shields.io/pypi/v/backrefs.svg?logo=pypi&logoColor=aaaaaa&labelColor=333333
[pypi-down]: https://img.shields.io/pypi/dm/backrefs.svg?logo=pypi&logoColor=aaaaaa&labelColor=333333
[pypi-link]: https://pypi.python.org/pypi/backrefs
[python-image]: https://img.shields.io/pypi/pyversions/backrefs?logo=python&logoColor=aaaaaa&labelColor=333333
[license-image-mit]: https://img.shields.io/badge/license-MIT-blue.svg?labelColor=333333
[license-link]: https://github.com/facelessuser/backrefs/blob/main/LICENSE.md
[donate-image]: https://img.shields.io/badge/Donate-PayPal-3fabd1?logo=paypal
[donate-link]: https://www.paypal.me/facelessuser

[re]: https://docs.python.org/3/library/re.html
[regex]: https://pypi.python.org/pypi/regex


A wrapper around re and regex that adds additional back references. 

Socket Acquires Coana to Bring Reachability Analysis to Every Appsec Team

backrefs

A wrapper around re and regex that adds additional back references.

facelessuser

(Experimental) An ambiguous license classifier was found.

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Ambiguous License Classifier

Source files are encoded using a non-standard text encoding.

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Package version is not a valid semantic version (semver).

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Bad semver

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Bad dependency semver

Source files contain bidirectional unicode control characters. This could indicate a Trojan source supply chain attack. See: trojansource.codes for more information.

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Bidirectional unicode control characters

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Bin script confusion

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

(Experimental) Copyleft license information was found.

What do I need to know about license files?

Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

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High CVE

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Debug access

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Deprecated license

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What is a typosquat?

Possible typosquat attack

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Dynamic require

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Empty package

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Name

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File dependency

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Filesystem access

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Wildcard dependency

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High entropy strings

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Unicode homoglyphs

Contains a dependency which resolves to a remote HTTP URL which could be used to inject untrusted code and reduce overall package reliability.

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HTTP dependency

Install scripts are run when the package is installed. The majority of malware in npm is hidden in install scripts.

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Install scripts

Package has an invalid manifest file and can cause installation problems if you try to use it.

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Invalid manifest file

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Invisible chars

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License change

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This package is not allowed per your license policy. Review the package's license to ensure compliance.

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License Policy Violation

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What's wrong with long strings?

Long strings

Package has recently undergone a major refactor. It may be unstable or indicate significant internal changes. Use caution when updating to versions that include significant changes.

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Major refactor

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Known malware

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Manifest confusion

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Medium CVE

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Modified license exception

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Modified license

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Network access

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New author

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Why is contributor and author data important?

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No bug tracker

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No repository

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backrefs

Backrefs

Documentation

License

Keywords

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backrefs

Backrefs

Documentation

License

Keywords

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