diff options
Diffstat (limited to 'node_modules/regex-cache/README.md')
| -rw-r--r-- | node_modules/regex-cache/README.md | 166 |
1 files changed, 0 insertions, 166 deletions
diff --git a/node_modules/regex-cache/README.md b/node_modules/regex-cache/README.md deleted file mode 100644 index 8c6601478..000000000 --- a/node_modules/regex-cache/README.md +++ /dev/null @@ -1,166 +0,0 @@ -# regex-cache [](https://www.npmjs.com/package/regex-cache) [](https://npmjs.org/package/regex-cache) [](https://npmjs.org/package/regex-cache) [](https://travis-ci.org/jonschlinkert/regex-cache) [](https://ci.appveyor.com/project/jonschlinkert/regex-cache) - -> Memoize the results of a call to the RegExp constructor, avoiding repetitious runtime compilation of the same string and options, resulting in surprising performance improvements. - -## Install - -Install with [npm](https://www.npmjs.com/): - -```sh -$ npm install --save regex-cache -``` - -* Read [what this does](#what-this-does). -* See [the benchmarks](#benchmarks) - -## Usage - -Wrap a function like this: - -```js -var cache = require('regex-cache'); -var someRegex = cache(require('some-regex-lib')); -``` - -**Caching a regex** - -If you want to cache a regex after calling `new RegExp()`, or you're requiring a module that returns a regex, wrap it with a function first: - -```js -var cache = require('regex-cache'); - -function yourRegex(str, opts) { - // do stuff to str and opts - return new RegExp(str, opts.flags); -} - -var regex = cache(yourRegex); -``` - -## Recommendations - -### Use this when... - -* **No options are passed** to the function that creates the regex. Regardless of how big or small the regex is, when zero options are passed, caching will be faster than not. -* **A few options are passed**, and the values are primitives. The limited benchmarks I did show that caching is beneficial when up to 8 or 9 options are passed. - -### Do not use this when... - -* **The values of options are not primitives**. When non-primitives must be compared for equality, the time to compare the options is most likely as long or longer than the time to just create a new regex. - -### Example benchmarks - -Performance results, with and without regex-cache: - -```bash -# no args passed (defaults) - with-cache x 8,699,231 ops/sec ±0.86% (93 runs sampled) - without-cache x 2,777,551 ops/sec ±0.63% (95 runs sampled) - -# string and six options passed - with-cache x 1,885,934 ops/sec ±0.80% (93 runs sampled) - without-cache x 1,256,893 ops/sec ±0.65% (97 runs sampled) - -# string only - with-cache x 7,723,256 ops/sec ±0.87% (92 runs sampled) - without-cache x 2,303,060 ops/sec ±0.47% (99 runs sampled) - -# one option passed - with-cache x 4,179,877 ops/sec ±0.53% (100 runs sampled) - without-cache x 2,198,422 ops/sec ±0.47% (95 runs sampled) - -# two options passed - with-cache x 3,256,222 ops/sec ±0.51% (99 runs sampled) - without-cache x 2,121,401 ops/sec ±0.79% (97 runs sampled) - -# six options passed - with-cache x 1,816,018 ops/sec ±1.08% (96 runs sampled) - without-cache x 1,157,176 ops/sec ±0.53% (100 runs sampled) - -# -# diminishing returns happen about here -# - -# ten options passed - with-cache x 1,210,598 ops/sec ±0.56% (92 runs sampled) - without-cache x 1,665,588 ops/sec ±1.07% (100 runs sampled) - -# twelve options passed - with-cache x 1,042,096 ops/sec ±0.68% (92 runs sampled) - without-cache x 1,389,414 ops/sec ±0.68% (97 runs sampled) - -# twenty options passed - with-cache x 661,125 ops/sec ±0.80% (93 runs sampled) - without-cache x 1,208,757 ops/sec ±0.65% (97 runs sampled) - -# -# when non-primitive values are compared -# - -# single value on the options is an object - with-cache x 1,398,313 ops/sec ±1.05% (95 runs sampled) - without-cache x 2,228,281 ops/sec ±0.56% (99 runs sampled) -``` - -## Run benchmarks - -Install dev dependencies: - -```bash -npm i -d && npm run benchmarks -``` - -## What this does - -If you're using `new RegExp('foo')` instead of a regex literal, it's probably because you need to dyamically generate a regex based on user options or some other 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._
\ No newline at end of file |