# lRegExp

Transparently create linear-time ([non-backtracking]) regular expressions.

[non-backtracking]: https://v8.dev/blog/non-backtracking-regexp

## Usage

This library exports a drop-in replacement for the built-in RegExp.

```shell
npm install @ericcornelissen/lregexp
```

```javascript
import RegExp from "@ericcornelissen/lregexp";
new RegExp("[linear]{6}");
```

## Why

Backtracking regular expressions can take exponential time to evaluate, leading
to the dreaded _ReDoS_ vulnerability. Linear-time regular expressions avoid this
by not backtracking.

## Caveats

Not all regular expression constructs are valid in a linear-time regular
expression and this library won't tell you your regular expression is
incompatible unless you run it with the non-backtracking engine, in which
case it throws an error.


Transparently create linear-time regular expressions. 

@ericcornelissen/lregexp

Transparently create linear-time regular expressions

ericcornelissen

lregexp

(Experimental) An ambiguous license classifier was found.

What is an ambiguous license classifier?

Ambiguous License Classifier

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

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Bad text encoding

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

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Bad semver

Package has dependencies with an invalid semantic version. This could be a sign of beta, low quality, or unmaintained dependencies.

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Bad dependency semver

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Bidirectional unicode control characters

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Bin script confusion

This Chrome extension includes a content script '{scriptFile}' that runs on websites matching '{matches}'.

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Chrome Extension Content Script

This Chrome extension requests access to '{host}'.

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Chrome Extension Host Permission

This Chrome extension uses the '{permission}' permission.

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Chrome Extension Permission

This Chrome extension requests broad access to websites with the pattern '{host}'.

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Chrome Extension Wildcard Host Permission

Semantic versions published out of chronological order.

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Chronological version anomaly

Project maintainer's SSH key has been compromised.

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Compromised SSH key

(Experimental) Copyleft license information was found.

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Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

Critical CVE

Contains a high severity Common Vulnerability and Exposure (CVE).

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High CVE

Uses debug, reflection and dynamic code execution features.

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Debug access

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Deprecated

(Experimental) Contains a known deprecated SPDX license exception.

What is a deprecated SPDX exception?

Deprecated SPDX exception

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

What is a typosquat?

Possible typosquat attack

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Dynamic require

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Empty package

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File dependency

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Filesystem access

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Wildcard dependency

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AI-detected potential malware

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AI-detected potential security risk

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Native code

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High entropy strings

Contains unicode homoglyphs which can be used in supply chain confusion attacks.

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Unicode homoglyphs

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HTTP dependency

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Invalid manifest file

Source files contain invisible characters. This could indicate source obfuscation or a supply chain attack.

What are invisible characters?

Invisible chars

(Experimental) Package license has recently changed.

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License change

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What is a license exception?

License exception

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

What is a license policy violation?

License Policy Violation

Contains long string literals, which may be a sign of obfuscated or packed code.

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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Medium CVE

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Low CVE

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Modified license exception

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What is a modified license?

Modified license

What is network access?

Network access

A new npm collaborator published a version of the package for the first time. New collaborators are usually benign additions to a project, but do indicate a change to the security surface area of a package.

What is new author?

New author

Package does not specify a list of contributors or an author in package.json.

Why is contributor and author data important?

No contributors or author data

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No bug tracker

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@ericcornelissen/lregexp

lRegExp

Usage

Why

Caveats

Keywords

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lRegExp

Usage

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Caveats

Keywords

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