In People v. Hansen (1994) 9 Cal.4th 300 (Hansen), the court explained it had not extended the merger doctrine beyond the context of assault, even if the underlying felony could be considered an integral part of or included in fact within the resulting homicide. ( Id. at p. 312.) The court held that a felony does not merge with a homicide if the act causing death was committed with a collateral and independent felonious purpose separate from the intent to inflict the injury that caused death. (Id. at p. 314.) The court concluded that discharging a firearm at an inhabited dwelling house does not merge with a resulting homicide and that the offense will support a second degree felony-murder conviction. (Id. at p. 316.) When the defendant in Hansen was sentenced, Penal Code section 12022.5, subdivision (a) provided, as it currently provides, that the firearm use enhancement specified in that subdivision could not be imposed if use of a firearm was an element of the offense of which the defendant was convicted. ( Hansen, supra, 9 Cal.4th at pp. 316-317.) Because second degree murder, considered in the abstract, does not include use of a firearm as an element, the court held that the defendant's sentence for second degree murder could be enhanced with a firearm use enhancement under Penal Code section 12022.5, subdivision (a) although the defendant may have been convicted on a felony-murder theory in which the underlying felony was discharging a firearm at an inhabited dwelling house. ( Hansen, supra, 9 Cal.4th at pp. 316-317.)