Re: A new era for Temporal
On Mon, 12 Apr 2010, Moritz Lenz wrote: Am 12.04.2010 03:47, schrieb Dave Rolsky: On Sun, 11 Apr 2010, Moritz Lenz wrote: I've planned to add such a module to the Perl 6 spec, but some comments on #perl6 suggested it should be kept out of core to prevent bloat. Still if the overall opinion is that Perl 6 should have such a module out of the box, I'll be happy to spec it. I think that having a standard, minimal API for this defined in core as a Date role would be ideal. I'm curious, why a role and not a class? No reason, really. I don't tihnk I understand the Perl 6 way well enough to make a good distinction. Mostly, I want there to be something simple that classes on CPAN6 can implement and build on. -dave /* http://VegGuide.org http://blog.urth.org Your guide to all that's veg House Absolute(ly Pointless) */
Re: r30398 - docs/Perl6/Spec/S32-setting-library
On Fri, 16 Apr 2010, pugs-comm...@feather.perl6.nl wrote: +=head2 Semi-internal methods + +[This section is severely conjectural] + +For efficient implementation of arithmetics on C objects, two more +methods are exposed: + +$d.daycount +Date.new-from-daycount(Int $daycount) I'd _really_ like to see this be based on Rata Die, which is January 1, 0001. See http://en.wikipedia.org/wiki/Rata_Die This epoch value is used as the basis for many calendrical calculations in the Calendarical Calculations book, and has in turn been used as the method for calendar conversion in the Perl 5 DateTime sweet. Exposing this value explicitly (rata-die-day-count) would be a wise decision, IMO. Also, "day-count", not "daycount" ;) -dave /* http://VegGuide.org http://blog.urth.org Your guide to all that's veg House Absolute(ly Pointless) */
Parrot 2.3.0 Released!
"Truth is what stands the test of experience."
- Albert Einstein
On behalf of the Parrot team, I'm proud to announce Parrot 2.3.0 "Samoan
Lory." Parrot (http://parrot.org/) is a virtual machine aimed at running
all dynamic languages.
Parrot 2.3.0 is available on Parrot's FTP site, or follow the download
instructions at http://parrot.org/download. For those who would like to
develop on Parrot, or help develop Parrot itself, we recommend using
Subversion on the source code repository to get the latest and best
Parrot code.
Parrot 2.3.0 News:
- Core
+ Allow passing parameters to the dynamic linker ('dlopen' improved)
+ loadlib opcode added
+ Calling conventions are now much more consistent, and follows
natural
semantics of handling arguments and return values
+ Recursive make for src/dynpmc removed
+ Datatype STRINGNULL for a single Null STRING added
+ config_lib.pasm replaced with config_lib.pir
- Platforms
+ Improved handling of new compilers
+ Cygwin packages will be updated again with Parrot releases
+ Fedora packages add desktop files
+ gzip and bzip2 compressed tar files for releases
- Tools
+ tapir executable added; tapir is a TAP test harness
+ Added TAP options --merge --ignore-exit
- Miscellaneous
+ 3 month cycle for supported releases
+ Review and vote of GSoC applications
Many thanks to all our contributors for making this possible, and our
sponsors for supporting this project. Our next scheduled release is 18
May 2010.
Enjoy!
Re: r30398 - docs/Perl6/Spec/S32-setting-library
On Tue, Apr 20, 2010 at 10:59 AM, Dave Rolsky wrote: > I'd _really_ like to see this be based on Rata Die, which is January 1, > 0001. See http://en.wikipedia.org/wiki/Rata_Die > To be clear, that's specifically January 1, 1 CE in the retrojected Gregorian calendar, which is the same day as January 1, 3 CE in the retrojected Julian calendar; noon UTC began Julian Day 1,721,426. You could also use the JD directly, but there's a subtle design decision lurking there. The JD is tied to UTC, and refers to a specific 24-hour period that is the same across the planet: JD 2,455,307 began 4 hours and 45 minutes ago as I write this, and will be over in 19 hours and 15 minutes, and that is a universal fact no matter whether it's currently Tuesday the 20th or already Wednesday the 21st where you are. An RD, in contrast, is not tied to a specific time zone, but is simply a numerical way to represent exactly the same concept as the date: whatever the Gregorian date "April 20, 2010" means, "RD 733,882" means the same thing. So on some parts of the planet its RD 733,882 and in others it's already RD 733,883. The RD is thus a better fit for the Date class, which is a representation of an abstract date, unanchored in spacetime. An integral JD number may be used to fit the same bill, but opens the possibility of confusion with the more typical anchored JD values (which might even be available from DateTime objects). The difference between them, or with any other epoch choice, is mostly just a matter of a constant which can be added or subtracted as needed, and to the degree that's true this is just bikeshed painting. But the part that isn't is important: I don't want to dilute what I see as the primary benefit of a Date object over a DateTime object that simply has its time fields zeroed, which is flexibility. The latter is still by implication tied to a specific swath of spacetime (e.g. midnight to midnight in some time zone), whereas the former is free to refer to whatever the human date designation can. -- Mark J. Reed
