super-expressive.macro

A macro to generate regular expressions at build-time with super-expressive.

You may like to watch this YouTube video to get an idea of what macros are and how to use them.

Motivation

Super Expressive is awesome, but it's a runtime library only.

Depending on the use case, Super Expressive is very useful for declaring the regular expressions, but when building the project, the final expression is preferred.

This library aims to be a drop-in replacement for Super Expressive where applicable - see restrictions.

Installation

npm install super-expressive.macro

yarn add super-expressive.macro

This library depends on super-expressive. Please make sure to install it.

Usage

To use macros, make sure to set up babel-plugin-macros.

Example

import SuperExpressive from 'super-expressive.macro'

const myRegex = SuperExpressive()
  .startOfInput.optional.string('0x')
  .capture.exactly(4)
  .anyOf.range('A', 'F')
  .range('a', 'f')
  .range('0', '9')
  .end()
  .end()
  .endOfInput.toRegex()

After compilation:

const myRegex = /^(?:0x)?([A-Fa-f0-9]{4})$/

Notice that the macro import disappeared after compilation ✨

The example folder contains the same code as above, but you can build it and see the result.

Check the super-expressive's detailed API for more examples. Don't forget to check the restrictions.

Restrictions

Because this plugin runs at build-time, there are some restrictions to its usage.

• You can't use dynamic variables inside the macro, all the params to its methods must be literals;
• You can't use constant variables inside the macro at the moment but there's an issue to track if this is possible as we improve this macro;
• You can't use [subexpressions] inside the macro at the moment but there's an issue to track if this is possible as we improve this macro;

Contributors

Thanks goes to these wonderful people (emoji key):

This project follows the all-contributors specification. Contributions of any kind welcome!

LICENSE

MIT