The proposal https://tc39.github.io/proposal-private-methods/ is on Stage 3.
Created attachment 370694 [details]
WIP - Patch
This patch is dependent on changes from https://bugs.webkit.org/show_bug.cgi?id=174212.
Created attachment 373050 [details]
This Patch does not apply to tree, since it is a diff from patch on https://bugs.webkit.org/show_bug.cgi?id=174212.
Created attachment 380859 [details]
This patch is the diff of private methods on top of class fields patch.
Comment on attachment 380859 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=380859&action=review
> + if (!m_privateNamesStack.size())
> + return;
Could this be an assertion?
You could probably drop this file if it's just whitespace changes.