get parameters name of a function

[mparsa]

Is there any function that gets the name of the function and returns the name of the parameters ?
For example I have a function like this :
(defun test (m n))
I want to get m and n. But I don't want the value of the n and m, Just the name of the parameter "m" and "n".

[Goheeca]

For a human readable output is the function describe.
Otherwise I recommend you to write a macro for that.
Here is a simple sketch:

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(defmacro my-defun (fname (&rest args) &body body)
  `(symbol-macrolet ((lambda-expr ',args))
      (defun ,fname ,args ,@body)))

Watch out! This is only a sketch it's not a hygienic macro and does a multiple evaluation of its arguments. It's only for defun construct and not for example lambda.
Usage:

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(my-defun plus (a b c)
  (format t "~a ~a" (+ a b c) lambda-expr))

[Goheeca]

Of course, you can use let instead of symbol-macrolet and it's more suitable.

[nuntius]

The CL standard does not specify any functions for this type of introspection.

Several CL implementations provide support for it. Search for "defimplementation arglist" in Slime's sources to see how.