Hello folks,
For Erik Naggum's memorial, I am putting my implementation of his
LOCAL-TIME concepts into public domain.
Ystok-Local-Time is a Common Lisp library for representing and
handling time zones, dates, and timestamps. This package partially
supports ISO 8601 format and provides localized read and print of date
and time.
The idea was originally based on the LOCAL-TIME concept proposed in
"The Long, Painful History of Time" by Erik Naggum (1965-2009) <http://
naggum.no/lugm-time.html>.
Ystok-Local-Time was also inspired by the Local-Time package by
onShore, Inc. available from http://alpha.onshore-devel.com/lisp-software/.
But Erik had criticized their open source implementation heavily.
For example, bignum-based operations were defeating the original
efficiency purpose of the LOCAL-TIME.
Taking the critique into account and after realizing drawbacks, the
fundamentals were redesigned in Ystok-Local-Time and code was
rewritten considerably.
The main feature is the following date/time type triplet:
- date corresponds to the DATE data type in SQL(ISO/IEC
9075:1999,2003).
- local-time corresponds to TIMESTAMP WITHOUT TIME ZONE.
- utc-time corresponds to SQL TIMESTAMP WITH TIME ZONE and contains an
explicit timezone offset.
The library was developed and tested on LispWorks for Windows 4.3,
4.4, 5.0.
The author has not tried to run the code on any *nix himself, though
unix-specific code from onShore is preserved "as is", see unix.lisp.
The latest version is at http://lisp.ystok.ru/ylocal-time/
Any customization targeted at other platforms and Lisp implementations
is welcome. Bug reports and suggestions are welcome.
--
Sincerely,
Dmitriy Ivanov
lisp.ystok.ru
divanov <·········@gmail.com> writes:
> For Erik Naggum's memorial, I am putting my implementation of his
> LOCAL-TIME concepts into public domain.
Do you know about this project?
<http://common-lisp.net/project/local-time/>
--
Luís Oliveira
http://student.dei.uc.pt/~lmoliv/
On Jun 25, 5:04 pm, ·············@deadspam.com (Luís Oliveira) wrote:
> Do you know about this project?
> <http://common-lisp.net/project/local-time/>
Yes, I have heard about it recently. I believe ystok-local-time
predates it a bit :-)
--
Sincerely,
Dmitriy Ivanov
lisp.ystok.ru
Hi Dmitriy, list!
It would be nice on you, Dmitry, to provide some info on differences
between
ylocal-time and other date-time libraries. I'm currently using some
customized version of
local-time and I'm interested in using the best date/time library
available.
On Jun 26, 2:01 pm, budden <···········@mail.ru> wrote:
> Hi Dmitriy, list!
> It would be nice on you, Dmitry, to provide some info on differences
> between
> ylocal-time and other date-time libraries. I'm currently using some
> customized version of
> local-time and I'm interested in using the best date/time library
> available.
I spent too much time learing date/time concepts and libraries 5-7
years ago and earlier. I don't think I have time to dive into someone
else's code now. So the comparison is left to the user as an
execise :-).
divanov <·········@gmail.com> writes:
> The main feature is the following date/time type triplet:
> - date corresponds to the DATE data type in SQL(ISO/IEC
> 9075:1999,2003).
> - local-time corresponds to TIMESTAMP WITHOUT TIME ZONE.
> - utc-time corresponds to SQL TIMESTAMP WITH TIME ZONE and contains an
> explicit timezone offset.
That seems like a singularly bad naming choice, then
(I'd kind of expect something called UTC-TIME to be UTC!)
On Jun 25, 4:28 pm, Paul Foley <····@below.invalid> (http://
public.xdi.org/=pf) wrote:
> > - utc-time corresponds to SQL TIMESTAMP WITH TIME ZONE and contains an
> > explicit timezone offset.
>
> That seems like a singularly bad naming choice, then
> (I'd kind of expect something called UTC-TIME to be UTC!)
An instance of utc-time does hold the UTC time value encoded in a way,
along with the timezone offset slot.
--
Sincerely,
Dmitriy Ivanov
lisp.ystok.ru