Re: [Scheme-reports] some questions on byte vectors + ports Alex Shinn 27 Jun 2012 22:05 UTC

On Wed, Jun 27, 2012 at 2:56 PM, Aubrey Jaffer <agj@alum.mit.edu> wrote:
>  | Date: Wed, 27 Jun 2012 14:14:02 -0700
>  | From: Alex Shinn <alexshinn@gmail.com>
>  |
>  | On Wed, Jun 27, 2012 at 2:10 PM, Aubrey Jaffer <agj@alum.mit.edu> wrote:
>  | >  | Date: Wed, 27 Jun 2012 10:04:21 -0700
>  | >  | From: Alex Shinn <alexshinn@gmail.com>
>  | >  |
>  | >  | On Wed, Jun 27, 2012 at 9:52 AM, Aubrey Jaffer <agj@alum.mit.edu> wrote:
>  | >  | > ...
>  | >  | > SLIB provides R4RS/R5RS Scheme code to accomplish these conversions in
>  | >  | > a way which is unaffected by host byte-order.  See:
>  | >  | > <http://people.csail.mit.edu/jaffer/slib/Byte_002fNumber-Conversions.html#Byte_002fNumber-Conversions>
>  | >  |
>  | >  | Note this is not truly portable in R4/R5 - you do need read-u8
>  | >  | and write-u8 provided by R6/R7.
>  | >
>  | > The SLIB conversions between numbers and byte-vectors do not require
>  | > read-u8 or write-u8.
>  |
>  | Oh, I thought you were referring to the I/O operators.  In that
>  | case, it's still not portable R4/R5 because these had no portable
>  | byte-vectors (without srfi-4 or one of the many array srfi's).
>
> The SLIB default implementation of byte-vectors is as arrays of bytes.
> The SLIB default implementation of arrays is portable R4RS/R5RS code
> which is included as the example implementation of SRFI-63,
> <http://srfi.schemers.org/srfi-63/srfi-63.html>.
>
> The SRFI-63 example code uses records (procedure calls; no macros);
> SLIB has a R4RS/R5RS compliant implementation of records at
> <http://savannah.gnu.org/cgi-bin/viewcvs/slib/slib/record.scm?rev=HEAD&content-type=text/vnd.viewcvs-markup>
>
> So you see Mr. Shinn, it's R4RS/R5RS-compliance all the way down.

Not down to the disk - everything is in in-memory Scheme
data structures and not at all addressing Wolfang's
needs, which is reading and writing these bytes from
files.

--
Alex

_______________________________________________
Scheme-reports mailing list
Scheme-reports@scheme-reports.org
http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports