7.5.40 SRFI-71 - Extended let-syntax for multiple values

This SRFI shadows the forms for let, let*, and letrec so that they may accept multiple values. For example:

(use-modules (srfi srfi-71))

(let* ((x y (values 1 2))
       (z (+ x y)))
  (* z 2))
⇒ 6

See the specification of SRFI-71.