[Sbcl-devel] make-instance and structures

[Stephen W. <wi...@st...>]

Greetings!

I do not doubt that the following is a known issue. On the off chance it
is not..

We have:

  * (sb-mop::generic-function-methods #'make-instance)

  (#<STANDARD-METHOD MAKE-INSTANCE (SYMBOL) {93EB881}>
   #<STANDARD-METHOD MAKE-INSTANCE (CLASS) {93EB899}>)

The spec defines a primary method specialized to STANDARD-CLASS instead of
CLASS.

It is not so much that the implementation misses the standard that compels me to
write.  Rather, it is:

  * (defstruct foo (a nil))

  FOO
  * (make-instance 'foo)

  #S(FOO :A 0)

The slot A is initialized to 0 instead of NIL.  In `downgrading' a class to a
struct I missed a call to MAKE-INSTANCE and thus produced a difficult bug.

Perhaps someone knows of a fix to one of the above problems?

Thanks,
Steve