TC39 Zone Proposalexample.md Examples Logging Zone class LoggingZoneSpec { constructor() { this.name = 'logging'; this.prefix = ''; } onInvoke(parentZoneDelegate, currentZone, targetZone, callback, applyThis, applyArg) { console.log(this.prefix + 'Enter Zone:', targetZone.name); this.prefix += ' '; try { return parentZoneDelegate.invoke(targetZone, callback, applyThis, applyArg); } finally { this.prefix = this.pref
