A string in C is entirely built upon convention; it exists in the words of a document only.

Common Lisp has a list class that you can specialize a CLOS method on.

Also:

  [1]> (typep nil 'list)
  T
  [2]> (typep '(a) 'list)
  T
  [3]> (typep 3 'list)
  NIL

And:

  [4]> (subtypep 'cons 'list)
  T ;
  T
  [5]> (subtypep 'null 'list)
  T ;
  T

So, kind of apples and oranges.

I was referring to John McCarthy's definition of a list. IIRC, Common lisp's list type includes both proper and unproper lists. (typep (cons 1 2) 'list) evaluates to true but (length (cons 1 2)) throws a type error (not a list).

I guess you could think of it as an "implicit type". I prefer to think of it as a data format rather than a data type. (It doesn't satisfy the meaning of "type" as C defines the word.)

char[n] (for constant n) is an array type. An object of type char[n] may or may not contain a string.