I've never heard them called "compact triples," but cranks fitting that moniker have existed for some time. 'Tis a question of bolt center diameter dimensions.

Once mountain bikes went mainstream, triple cranks with 110/74 bcd came into existence and became pretty much the touring bike standard. The 110 bcd is what "compact doubles" use now, so you could have a middle chainring down to 34 teeth and, with the 74 bcd inner, you can get down to at least 24 and maybe smaller. Shimano used to make bazillions of these. I have this kind of crank (Ritchie labeled, bought at Rivendell) on my Paramount, running 46/36/26 chainrings and an 11-26 9-speed cassette. Serious gear range, and easy to get lower if need be.

Mountain bike cranks have since gone to four-bolt chainrings with smaller numbers of teeth, and since I have zero interest in them I can't tell you anything about them.

The crank you have, acpeeps, would technically not be what I would call a "compact triple." It is what has come in the past ten years or so to be the standard road triple, with either 135 bcd (Campy) or 130 bcd (pretty much everyone else) for the outer two chainrings and, I believe, a 74 bcd for the inner. The 50 tooth large 'ring is not the most common for such set-ups (52 or 53 seems to be more common), but it is certainly not unheard of - bigbossman has a 50 on a Campy triple.