Issue: WITH-COMPILATION-UNIT (Version 1)

[Eric Benson <eb@lucid.com>]

  Note that if nested, either lexically or dynamically, only the
  outer call to WITH-COMPILATION-UNIT has any effect.

Lexical nesting doesn't matter, only dynamic.  Any example of
lexical nesting without dynamic nesting would be utterly bizarre
anyway.

  (DEFUN COMPILE-FILES (&REST FILES)
    (WITH-COMPILATION-UNIT ()
      (MAPCAR #'(LAMBDA (FILE) (COMPILE-FILE FILE)) FILES)))

I don't think you meant to put () in there.

Lucid implements this in 3.0, as WITH-DEFERRED-WARNINGS.  I support
this proposal.