On 15/03/2015, at 4:16 PM, Mark Cox wrote:

G'day,

CMUCL does not shadow the compiler macro function present in the global environment when introducing a function with the same name in the current lexical environment. This is demonstrated with the following example:

(defun square (x) (expt x 2))

(define-compiler-macro square (&whole form arg) (declare (ignore arg)) form)

(defun test () (flet ((square (arg) (declare (ignore arg)) (write "SQUARE!"))) (macrolet ((my-square (arg &environment env) (if (compiler-macro-function 'square env) `(function square) nil))) (my-square 1))))

(test) => #<Function (FLET SQUARE TEST) {48704B89}>

Forget this. I have miscomprehended the definition of MACROLET in the Hyperspec. The macro-expansion functions defined by macrolet are defined in the lexical environment in which the macrolet form appears. Declarations and macrolet and symbol-macrolet definitions affect the local macro definitions in a macrolet, but the consequences are undefined if the local macro definitions reference any local variable or function bindings that are visible in that lexical environment. Sorry. Mark