sequence

(sequence coll) / (sequence xform coll...)

Of one collection, its seq (a lazy seq itself). With a transducer, the collections step through it one element at a time: several step in lockstep to the shortest, each row spread as the step's arguments (only map takes several). A lazy input answers a lazy seq, so take of an infinite one terminates; a strict input answers a strict list. The empty result is nil, where the oracle prints (). As a value one or more arguments.