Let's stop referring to the man who killed five Dallas police officers and wounded seven others and two civilians as a "sniper" or to what he did as a "sniper attack."
He was a "gunman," a "killer," a "shooter" and several other words you can probably come up with. It was an "ambush" as well as an "attack."
Yes, it appears he at times was firing from hidden positions and from above the street. But he also shot at least one officer from point-blank range. Reporting since the attack indicates he moved quickly from one position to the next. He wasn't a "sniper" in the sense that most people have come to understand that word — an expert who lies in wait and then methodically fires single shots from a long distance.