Hi,
I have encountered a problem with the sharp-m reader macro function.
The sharp-m reader macro function (lambda in grid/functions.lisp,
l. 202) uses the function cl:read-delimited-list to read the macro
arguments. However, when cl:*read-suppress* is true,
read-delimited-list always returns nil (See *read-suppress* in CLHS.)
That value is then (wrongly) passed to grid:check-initial-contents,
which (rightly) signals the error "Initial-contents specified as
NIL."
The following code can be used to observe the behaviour. No matter
what (valid or invalid) code is inside the sharp-m parentheses, the
error will be signaled.
(let ((*read-suppress* t))
(with-input-from-string (stream "#m(1 2 3)")
(read stream)))
The solution is to call read-delimited-list and then check if we have
to ignore its return value with "(unless *read-suppress* ...)". Patch
attached.
By the way, how I encountered this issue: When I compile a file with
C-c C-k and the compilation yields warnings or notes, the Slime/SBCL
combination seems to re-read the file with *read-suppress*. Any
sharp-m macro that is then read triggers the error. Try with:
#m(1 2 3)
(defun foo (bar)) ; unused variable style-warning
Comments?
Martin