Re: Overflows (lisp fixnum-bignum conversion)

[bobduff@world.std.com (Robert A Duff)]

In article <Pine.SUN.3.96.970405054237.22894A-100000@eskimo.com>,
Clayton Weaver  <cgweav@eskimo.com> wrote:
>Std lisp limits array indexes to fixnums. Lisp can transparently cast the
>overflowing representation from fixnum to bignum, but it will still error
>if it tries to allocate an array ("vector") with an index size beyond the
>fixnum bound, unless you have a custom handler for that case that either
>changes the array to some other storage type or virtualizes the data
>structure into an array of arrays, and sets a flag that whatever function
>accesses that array can read to change its lookup method.

I won't complain if I can't allocate an array bigger than 2**32 bytes on
a machine that has a 32-bit address space.  That's a lot different from
telling me I can't allocate a 1000-bit integer on such a machine.

- Bob