method WritableBase.prototype.emit
#WritableBase.prototype.emit(event: "close"): boolean
#WritableBase.prototype.emit(event: "drain"): boolean
#WritableBase.prototype.emit(event: "error",err: Error,): boolean
#WritableBase.prototype.emit(event: "finish"): boolean
#WritableBase.prototype.emit(event: "pipe",src: Readable,): boolean
#WritableBase.prototype.emit(event: "unpipe",src: Readable,): boolean