potentially changing factors. When your function creates a string based on user inputs and passes it to the `RegExp` constructor, regex-cache caches the results. The next time the function is called if the key of a cached regex matches the user input (or no input was given), the cached regex is returned, avoiding unnecessary runtime compilation. Using the RegExp constructor offers a lot of flexibility, but the runtime compilation comes at a price - it's slow. Not specifically because of the call to the RegExp constructor, but **because you have to build up the string before `new RegExp()` is even called**. ## About ### Contributing Pull requests and stars are always welcome. For bugs and feature requests, [please create an issue](../../issues/new). ### Contributors | **Commits** | **Contributor** | | --- | --- | | 31 | [jonschlinkert](https://github.com/jonschlinkert) | | 1 | [MartinKolarik](https://github.com/MartinKolarik) | ### Building docs _(This project's readme.md is generated by [verb](https://github.com/verbose/verb-generate-readme), please don't edit the readme directly. Any changes to the readme must be made in the [.verb.md](.verb.md) readme template.)_ To generate the readme, run the following command: ```sh $ npm install -g verbose/verb#dev verb-generate-readme && verb ``` ### Running tests Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command: ```sh $ npm install && npm test ``` ### Author **Jon Schlinkert** * [github/jonschlinkert](https://github.com/jonschlinkert) * [twitter/jonschlinkert](https://twitter.com/jonschlinkert) ### License Copyright © 2017, [Jon Schlinkert](https://github.com/jonschlinkert). Released under the [MIT License](LICENSE). *** _This file was generated by [verb-generate-readme](https://github.com/verbose/verb-generate-readme), v0.6.0, on September 01, 2017._