To be excruciatingly explicit: That code is 51 years old. Nobody writing Lisp now writes code that looks like that. Lisp environments are no longer based around

To be excruciatingly explicit: That code is 51 years old. Nobody writing Lisp now writes code that looks like that. Lisp environments are no longer based around punch cards and computers the size of a row of filing cabinets with the computational power of a fifteen-year-old cell phone. Trying to judge what Lisp is from that code is akin to trying to judge what airplanes are from something the Wright brothers built in their bicycle shop.