TXR Lisp:

  (defmacro ogogmad (:match)
    (() ())
    (((var @var @init))
     ^(progn ,init nil))
    ((@single)
     single)
    (((var @var @init) . @rest)
     ^(let ((,var ,init)) (ogogmad ,*rest)))
    ((@first . @rest)
     ^(progn ,first (ogogmad ,*rest))))


  1> (expand '(ogogmad (var a 4) (var b 5) (+ a b)))
  (let ((a 4))
    (let ((b 5))
      (+ a b)))
  2> (expand '(ogogmad))
  nil
  3> (expand '(ogogmad 42))
  42
  4> (expand '(ogogmad (var a 42)))
  nil
  5> (expand '(ogogmad (var a (print 42))))
  (progn (print 42)
    ())
  6> (ogogmad (var a 4) (var b 5) (+ a b))
  9

:match is a new kind of macro, called a parameter list macro, that I invented. defmacro doesn't know anything about pattern matching. Parameter list macros are expanded in any function/lambda or macro parameter list situation. The :match macro assumes that the function's body consists of pattern matching clauses. It infers the parameters from it, which get substituted.