Registry / serialization / babel-plugin-transform-regex

babel-plugin-transform-regex

library6.1.0jsnpmunverified

A Babel plugin that transpiles Regex+ template tag (`regex`…``) calls into native RegExp literals at build time. Current stable version is 6.1.0, updated January 2025. Releases are tied to the base Regex+ library. Key differentiators: eliminates runtime dependency, zero runtime cost, supports modern regex features (atomic groups, subroutines, definition groups, Unicode sets). Designed for Node.js and browser bundlers using Babel.

serialization

npm install babel-plugin-transform-regex

github ↗package ↗

INSTALL

IMPORT

SIG · BABEL-PLUGIN-TRANS

babel-plugin-transform-regex

serializationjavascriptv6.1.0

Install

—

Import

—

Disk

—

Pass rate

0/ 6

Env Coverage0 / 6

glibc

18–22

musl

18–22

Install & Compatibility

Where this runs

tested against v? · npm install

Install × environment matrix

Each cell = how many times install + import succeeded across repeated harness runs. Partial = flaky.
glibc = Debian/Ubuntu slim · musl = Alpine Linux

musl

node 18–226 runs

build_error

glibc

node 18–226 runs

build_error

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

default

✓ import plugin from 'babel-plugin-transform-regex'

✗ const plugin = require('babel-plugin-transform-regex')

ESM-only with default export. CommonJS require not supported.

removeImport

✓ // In .babelrc: { "plugins": [["babel-plugin-transform-regex", { "removeImport": true }]] }

✗ import { removeImport } from 'babel-plugin-transform-regex'

This is a Babel plugin option, not an exported symbol. Pass via plugin options object.

regex

✓ import { regex } from 'regex'; const r = regex`^abc$`;

✗ import regex from 'regex'; const r = regex`^abc$`;

Regex+ exports `regex` as a named export, not default. The Babel plugin transforms these tagged template literals.

Demonstrates setting up the Babel plugin and transforming a Regex+ template to a native RegExp literal with flag v.

// Install: npm install --save-dev babel-plugin-transform-regex regex // .babelrc: { "plugins": ["babel-plugin-transform-regex"] } // source.js: import { regex } from 'regex'; const ipv4 = regex` ^ \g<byte> (\.\g<byte>){3} $ (?(DEFINE) (?<byte> 2[0-4]\d | 25[0-5] | 1\d\d | [1-9]?\d) ) `; // After Babel transform: const ipv4 = /^(?:2[0-4]\d|25[0-5]|1\d\d|[1-9]?\d)(?:\.(?:2[0-4]\d|25[0-5]|1\d\d|[1-9]?\d)){3}$/v;

Debug

Known issues

breakingv4.3.0 changed the default flag for generated regexes from u to v (unicodeSets).

fix

Ensure target environments support flag v or use option `disableUnicodeSets: true` to fall back to flag u.

affects: >=4.3.0

deprecatedOption `disableUnicodeSets` was added in v4.0.1 to replace the old behavior of always using flag u.

fix

Use `disableUnicodeSets: true` if you need to avoid flag v in the output.

affects: >=4.0.1

gotchaThe plugin only transforms static `regex` tagged templates without dynamic interpolation. Variables or complex expressions inside the template are left untransformed.

fix

Ensure all interpolated values are inline literals (strings, numbers, regexes) or `pattern` tags. Otherwise, the `regex` call remains at runtime.

affects: >=4.0.0

gotchaThe `optimize` option (experimental) uses regexp-tree optimizer which may produce incorrect results for flag-v-only syntax like nested character classes.

fix

Test output thoroughly when using `optimize`. Consider not using it for complex patterns.

affects: >=4.1.0

Errors

Common errors & fixes

Cannot find module 'regex'

Missing runtime dependency `regex` when the plugin is not used or some templates are not transformed.

fix

Install `regex` as a dependency: npm install regex

Error: [BABEL] unknown plugin 'babel-plugin-transform-regex' specified in

Plugin is not installed as a devDependency.

fix

Run: npm install --save-dev babel-plugin-transform-regex

Uncaught SyntaxError: Invalid regular expression: invalid flag v

Target environment does not support flag v (unicodeSets), but plugin outputs regexes with /v.

fix

Use Babel's @babel/plugin-transform-unicode-sets-regex or set `disableUnicodeSets: true` in plugin options.

Upgrade

Version history

6.1.0latest on npm

Audit

Dependencies

regexrequiredBase regex+ library used for transformation logic

Agent activity

14 hits · last 30 days

node

OpenAI (training)

Resources

githubhttps://github.com/slevithan/babel-plugin-transform-regex ↗

packagehttps://www.npmjs.com/package/babel-plugin-transform-regex ↗