ECMAScript 2018(ES9) Features

Major new features:

• Asynchronous Iteration (Domenic Denicola, Kevin Smith)
• Rest/Spread Properties (Sebastian Markbåge)

New regular expression features:

• RegExp named capture groups (Gorkem Yakin, Daniel Ehrenberg)
• RegExp Unicode Property Escapes (Mathias Bynens)
• RegExp Lookbehind Assertions (Gorkem Yakin, Nozomu Katō, Daniel Ehrenberg)
• s (dotAll) flag for regular expressions (Mathias Bynens)

Other new features:

• Promise.prototype.finally() (Jordan Harband)
• Template Literal Revision (Tim Disney)