RegExp.prototype.count

kai zhu kaizhu256 at gmail.com
Sat Jan 12 22:29:15 UTC 2019


a common use-case i have is counting newlines in largish (> 200kb) embedded-js files, like this real-world example [1].  ultimately meant for line-number-preservation purposes in auto-lint/auto-prettify tasks (which have been getting slower due to complexity).

would a new RegExp count-method like ```(/\n/g).count(largeCode)``` be significantly more efficient than existing ```largeCode.split("\n").length - 1``` or ```largeCode.replace((/[^\n]+/g), "").length```?

-kai

[1] calculating and reproducing line-number offsets when linting/autofixing files
https://github.com/kaizhu256/node-utility2/blob/2018.12.30/lib.jslint.js#L7377 <https://github.com/kaizhu256/node-utility2/blob/2018.12.30/lib.jslint.js#L7377>
https://github.com/kaizhu256/node-utility2/blob/2018.12.30/lib.jslint.js#L7586 <https://github.com/kaizhu256/node-utility2/blob/2018.12.30/lib.jslint.js#L7586>

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20190112/dd294e8c/attachment.html>


More information about the es-discuss mailing list