Hah, that was actually ES5 ;-) but I assure you the entire JS community was celebrating. :)
I actually think C# is a better language than JS, but it's nice to see how they get the best features from each other.
Re:New Features in C# 7.0
by nulagrithom on Thursday March 09, 2017 @10:00PM
(#13835978)
ES6 actually! Pretty recent: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...
It's fun to see how languages influence each other.