walker lambda-list parsingnaïve

[Christophe Rhodes]

 affects sbcl
 status confirmed
 importance low
 tag walker lambda
 done

The walker doesn't do any sequential processing of bindings (for
&optional, &key, &aux). In the test framework of walk.impure.lisp

  (with-output-to-string (*standard-output*)
    (take-it-out-for-a-test-walk
      (lambda (&aux (a 1) (b a)) (declare (special a)) b)))
  "Form: (LAMBDA (&AUX (A 1) (B A)) (DECLARE (SPECIAL A)) B) Context: EVAL
   Form: 1 Context: EVAL
   Form: A Context: EVAL
   Form: B Context: EVAL; lexically bound
   (LAMBDA (&AUX (A 1) (B A)) (DECLARE (SPECIAL A)) B)"

the A line should have both “lexically bound” and “declared special” by
it.

Fixing this would share code with the hairy-specials test case
which currently exists in the walker test suite.