On Tue, 27 Feb 2024 05:02:58 -0500, James Kuyper wrote:

> On 2/26/24 18:20, Lawrence D'Oliveiro wrote:
>
>> On Mon, 26 Feb 2024 11:24:29 -0700, Joe Pfeiffer wrote:
>>
>>> Lawrence D'Oliveiro <ldo@nz.invalid> writes:
>>>
>>>> Easter, Christmas ... both ancient pagan festivals co-opted by the
>>>> Christians and given an invented meaning under their ideology, for
>>>> their own propaganda purposes.
>>>
>>> While that unquestionably true of Christmas, Easter very clearly comes
>>> from Passover.
>>
>> Easter bunny? Eggs? Both fertility symbols, associated with (northern)
>> spring and the beginning of the planting season? And both with origins
>> older than Christianity and Judaism combined?
>>
>> Somehow I doubt it.
>
> He was not talking about Easter customs, he was talking about the
> *definition" of Easter ...

In that case, that argument would also apply to the “definition” of
Christmas. So that what was “unquestionably true of Christmas” (as stated
above) must be the date. Which it is not.

On 2/27/24 17:48, Lawrence D'Oliveiro wrote:
> On Tue, 27 Feb 2024 05:02:58 -0500, James Kuyper wrote:
>
>> They were not co-opting a pagan date - they were trying to be MORE
>> correct than the Jews as to the timing of Passover.
>
> Religion is a matter of belief, not fact. Trying to be “more correct” than
> official religious authorities has a name: “heresy”.

Actually, no. The Christians had fully separated from Judaism by that
time - they no longer accepted the authority of Jewish religious
authorities. That is why it was considered so annoying to many
Christians that they had to go to Jewish religious authorities to
determine the correct timing for a Christian religious celebration. The
Council of Nicaea was where they officially decided that they didn't
need to do that anymore.

Whether or not it's heresy is also irrelevant to the point under debate:
whether the date of Easter was co-opted from a pagan religion. It wasn't
(you might be thinking of Christmas, which was so co-opted).

Incidentally, when the rules for determining how a calendar system
should work have been formalized, whether or not those rules have been
followed becomes a matter of fact, not a matter of belief or opinion.
Whether that calendar system should be used, whether the holy days of a
given religion should be celebrated according to that calendar are all
matters of opinion. Whether those rules had been formalized and followed
is not. I personally have not delved into the historical evidence deeply
enough to have an opinion on that issue - precisely because that issue
is irrelevant to the point under discussion. The timing of the Easter
celebration had nothing to do with any pagan religion.

On Tue, 27 Feb 2024 19:06:22 -0500, James Kuyper wrote:

> On 2/27/24 17:48, Lawrence D'Oliveiro wrote:
>
>> On Tue, 27 Feb 2024 05:02:58 -0500, James Kuyper wrote:
>>
>>> They were not co-opting a pagan date - they were trying to be MORE
>>> correct than the Jews as to the timing of Passover.
>>
>> Religion is a matter of belief, not fact. Trying to be “more correct”
>> than official religious authorities has a name: “heresy”.
>
> Actually, no. The Christians had fully separated from Judaism by that
> time - they no longer accepted the authority of Jewish religious
> authorities.

Or rather, the ones that still did were the ones considered “heretics”.

> whether the date of Easter was co-opted from a pagan religion. It wasn't

Nobody said it was.

On 2/27/24 19:11, Lawrence D'Oliveiro wrote:
> On Tue, 27 Feb 2024 19:06:22 -0500, James Kuyper wrote:
....
>> Actually, no. The Christians had fully separated from Judaism by that
>> time - they no longer accepted the authority of Jewish religious
>> authorities.
>
> Or rather, the ones that still did were the ones considered “heretics”.

Each side considered the other heretics. Heresy is a normally a two-way
accusation.

>> whether the date of Easter was co-opted from a pagan religion. It wasn't

You were the one who interrupted a discussion of the date of Easter by
claiming that Easter had been co-opted from pagan celebrations. Many of
the customs followed during Easter were co-opted, but not the date,
which rendered your comment a non-sequitur.

On 2/27/24 17:50, Lawrence D'Oliveiro wrote:
> On Tue, 27 Feb 2024 05:02:58 -0500, James Kuyper wrote:
....
>> He was not talking about Easter customs, he was talking about the
>> *definition" of Easter ...
>
> In that case, that argument would also apply to the “definition” of
> Christmas. So that what was “unquestionably true of Christmas” (as stated
> above) must be the date. Which it is not.

No, the date of Christmas was co-opted from a pagan Roman celebration.
The date of Easter was based upon Jewish traditions for Passover. With
modifications, to be sure - but those modifications were not co-opted
from pagan religions, they were due to a disagreement about the details
of the rules for the Hebrew calendar.

Lew Pitcher <lew.pitcher@digitalfreehold.ca> writes:

> On Sat, 24 Feb 2024 21:15:56 +0000, Mike Sanders wrote:
>
>> Calculate the date of Easter Sunday or Good Friday:
>>
>> https://busybox.neocities.org/notes/is-easter-or-goodfriday.txt
>
> I don't have the expertise to discuss whether or not your code
> properly implements the calculations necessary to determine the
> date of Good Friday and/or Easter. However, I /do/ have some
> expertise on writing understandable code.
>
> My suggestions, with respect to your program, would be to
> a) name your objects with relevant, understandable names
> You code uses quite a lot of meaningless one-letter
> objects, and it is difficult to keep track of the
> purpose of the calculations using them.
> b) Don't place your calculations /in/ the object initializations.
> Doing so obfuscates the intent of the logic, and makes
> problem determination and resolution difficult.

I urge those making these suggestions to have a go at doing both. I
suspect the result will be far less understandable.

> Otherwise, it /appears/ to do the job. Good first attempt.

--
Ben.

On 28/02/2024 01:41, James Kuyper wrote:
> On 2/27/24 17:50, Lawrence D'Oliveiro wrote:
>> On Tue, 27 Feb 2024 05:02:58 -0500, James Kuyper wrote:
> ...
>>> He was not talking about Easter customs, he was talking about the
>>> *definition" of Easter ...
>>
>> In that case, that argument would also apply to the “definition” of
>> Christmas. So that what was “unquestionably true of Christmas” (as stated
>> above) must be the date. Which it is not.
>
> No, the date of Christmas was co-opted from a pagan Roman celebration.
> The date of Easter was based upon Jewish traditions for Passover. With
> modifications, to be sure - but those modifications were not co-opted
> from pagan religions, they were due to a disagreement about the details
> of the rules for the Hebrew calendar.

Exactly.

There is clear Biblical justification for saying that the key Christian
religious events connected with Easter (centring on Jesus' claimed death
and resurrection) have a date directly related to the Jewish Passover at
that time. There is no Biblical justification for suggesting that the
the religious events of Christmas (the birth of Jesus) occurred in the
middle of winter or at any other particular time. (And there is no
evidence for any of this from non-Biblical sources, including, AFAIK,
other early Christian writings.) The date set for Christmas is thus
completely arbitrary from the religious viewpoint - it was picked to
co-opt existing mid-winter festivals.

You could go further back if you like - you could reasonably argue that
the date for the Jewish Passover was co-opted from older Canaanite
spring festivals. Basically, every culture and religion has had a
variety of festivals, and mid-winter, spring, mid-summer and autumn
(harvest time) are peaks for these. And every culture and religion that
has spread to other areas has either merged their festivals, co-opted
them, or overridden them, adapting old traditions and inventing new ones.

On Tue, 27 Feb 2024 19:24:05 -0500, James Kuyper wrote:

> You were the one who interrupted a discussion of the date of Easter by
> claiming that Easter had been co-opted from pagan celebrations. Many of
> the customs followed during Easter were co-opted, but not the date,
> which rendered your comment a non-sequitur.

Remember, you were the one who said that “the point under debate” was
“whether the date of Easter was co-opted from a pagan religion”. Not me.

Lawrence D'Oliveiro <ldo@nz.invalid> writes:
> On Tue, 27 Feb 2024 19:24:05 -0500, James Kuyper wrote:
>
>> You were the one who interrupted a discussion of the date of Easter by
>> claiming that Easter had been co-opted from pagan celebrations. Many of
>> the customs followed during Easter were co-opted, but not the date,
>> which rendered your comment a non-sequitur.
>
> Remember, you were the one who said that “the point under debate” was
> “whether the date of Easter was co-opted from a pagan religion”. Not me.

Here's your article from Feb 24:

From: Lawrence D'Oliveiro <ldo@nz.invalid>
Newsgroups: comp.lang.c
Subject: Re: Calculate date of Easter or Good Friday
Date: Sat, 24 Feb 2024 23:02:36 -0000 (UTC)
Message-ID: <urdsic$1e8e4$6@dont-email.me>

On Sat, 24 Feb 2024 23:57:16 +0100, Janis Papanagnou wrote:

> ... and that there's not a unique definition of Easter.

Easter, Christmas ... both ancient pagan festivals co-opted by the
Christians and given an invented meaning under their ideology, for their
own propaganda purposes.

Just like they took a lot of existing pagan deities (e.g. in Celtic lands)
and reinvented them as “saints”.

But I suggest that the point should never have been under debate here,
because it has nothing to do with C. (C code that calculates the date
of Easter is topical here; debates about holidays being co-opted from
pagan religions are not.)

--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Medtronic
void Void(void) { Void(); } /* The recursive call of the void */

On 2024-02-28, Keith Thompson <Keith.S.Thompson+u@gmail.com> wrote:
> because it has nothing to do with C. (C code that calculates the date
> of Easter is topical here; debates about holidays being co-opted from
> pagan religions are not.)

Easter is topical here to the extent that this is a sort island,
which is rumoured to be inhabited by cannibals.

--
TXR Programming Language: http://nongnu.org/txr
Cygnal: Cygwin Native Application Library: http://kylheku.com/cygnal
Mastodon: @Kazinator@mstdn.ca

On 2/28/24 15:47, Lawrence D'Oliveiro wrote:
> On Tue, 27 Feb 2024 19:24:05 -0500, James Kuyper wrote:
>
>> You were the one who interrupted a discussion of the date of Easter by
>> claiming that Easter had been co-opted from pagan celebrations. Many of
>> the customs followed during Easter were co-opted, but not the date,
>> which rendered your comment a non-sequitur.
>
> Remember, you were the one who said that “the point under debate” was
> “whether the date of Easter was co-opted from a pagan religion”. Not me.

You're right. That was a misstatement. The point under debate was the
timing of Easter. You're assertion that Easter had been co-opted from
pagan religions would have been relevant if you'd been claiming that the
date of Easter was one of the things that had been co-opted. It would
have been a false claim, but a relevant one. A person could be excused
for thinking that you'd intended to make a relevant comment. However,
you never made that particular assertion, rendering the comment you did
make a non-sequitur. I apologize for mis-characterizing what was wrong
with your comment.

vallor <vallor@cultnix.org> writes:

>> [...]
>
> ncal(1) has the -e and -o options for both Easters. I went looking
> for the source of the Easter-computation code, found one copy here:
>
> https://github.com/lattera/freebsd/blob/master/lib/libcalendar/easter.c
>
> On Ubuntu with source repositories enabled, one can get the BSD
> ncal (with its bundled libcalendar) with
>
> $ apt-get source ncal
>
> I really wish the function easterg() was commented better.
>
> /* Compute Easter Sunday in Gregorian Calendar */
> date *
> easterg(int y, date *dt)
> {
> int c, i, j, k, l, n;
>
> n = y % 19;
> c = y / 100;
> k = (c - 17) / 25;
> i = (c - c/4 -(c-k)/3 + 19 * n + 15) % 30;
> i = i -(i/28) * (1 - (i/28) * (29/(i + 1)) * ((21 - n)/11));
> j = (y + y/4 + i + 2 - c + c/4) % 7;
> l = i - j;
> dt->m = 3 + (l + 40) / 44;
> dt->d = l + 28 - 31*(dt->m / 4);
> dt->y = y;
> return (dt);
> }
>
> The code is 27 years old. I will not pretend to understand it.
> (Yet?)

Seems like bad style to have two assignments to 'i'. Easily
fixable simply by adding another variable.

Ben Bacarisse <ben.usenet@bsb.me.uk> writes:

> Lew Pitcher <lew.pitcher@digitalfreehold.ca> writes:
>
>> On Sat, 24 Feb 2024 21:15:56 +0000, Mike Sanders wrote:
>>
>>> Calculate the date of Easter Sunday or Good Friday:
>>>
>>> https://busybox.neocities.org/notes/is-easter-or-goodfriday.txt
>>
>> I don't have the expertise to discuss whether or not your code
>> properly implements the calculations necessary to determine the
>> date of Good Friday and/or Easter. However, I /do/ have some
>> expertise on writing understandable code.
>>
>> My suggestions, with respect to your program, would be to
>> a) name your objects with relevant, understandable names
>> You code uses quite a lot of meaningless one-letter
>> objects, and it is difficult to keep track of the
>> purpose of the calculations using them.
>> b) Don't place your calculations /in/ the object initializations.
>> Doing so obfuscates the intent of the logic, and makes
>> problem determination and resolution difficult.
>
> I urge those making these suggestions to have a go at doing both. I
> suspect the result will be far less understandable.

I have the same reaction regarding point (b). Regarding
point (a), I have mostly the same reaction, although in some
cases I think there are meaningful names that could be given.
Whether it is better to do that by changing variable names or
by describing what's going on in a block comment is another
matter.

In my view the key issue here is not what names are used but the
structure of the algorithm. Someone has taken a complicated set
of integer relationships and put them into a meat grinder, with
the result being a method that is (perhaps) computationally
efficient but horribly difficult to follow. If the goal is
understandability, I suggest taking a different approach so that
both the method and the code itself are directly comprehensible.

Lew Pitcher <lew.pitcher@digitalfreehold.ca> writes:

[minor editing]

>> On 25/02/2024 18:39, Lew Pitcher wrote:
>>
>>> On Sat, 24 Feb 2024 21:15:56 +0000, Mike Sanders wrote:
>>>
>>>> Calculate the date of Easter Sunday or Good Friday:
>>>>
>>>> https://busybox.neocities.org/notes/is-easter-or-goodfriday.txt
>>>
>>> My suggestions, with respect to your program, would be to
>>> [...]
>>> b) Don't place your calculations /in/ the object initializations.
>>> Doing so obfuscates the intent of the logic, and makes
>>> problem determination and resolution difficult.

Minor comment: normally I am used to the term "logic" to mean
how control structures are used, not simply the order of
otherwise sequential program elements. However I think I
understand what you mean so let's ignore that question.

> I base my suggestion on the OP's source:
> int isEasterOrGoodFriday(const struct tm *now, int checkGoodFriday) {
>
> int Y = now->tm_year + 1900; // correcting the year
> int a = Y % 19;
> int b = Y / 100;
> int c = Y % 100;
> int d = b / 4;
> int e = b % 4;
> int f = (b + 8) / 25;
> int g = (b - f + 1) / 3;
> int h = (19 * a + b - d - g + 15) % 30;
> int i = c / 4;
> int k = c % 4;
> int L = (32 + 2 * e + 2 * i - h - k) % 7;
> int m = (a + 11 * h + 22 * L) / 451;
> int month = (h + L - 7 * m + 114) / 31;
> int day = ((h + L - 7 * m + 114) % 31) + 1;
>
> if (checkGoodFriday) {
> [rest of code elided]
>
> The program code /depends/ on the specific order of
> the declarations: <<Y>> /must/ be declared before <<a>>,
> <<a>> /must/ be declared before <<h>>, etc.
>
> If some good-meaning (or unknowledgable) maintainer decides to
> reorder or consolidate the above declarations, the program
> either fails or gives erroneous results.

If variables are declared separately, without any initializers,
and all assignments are done after all the declarations, then the
assignment statements can be arbitrarily reordered and still get
a compilable program. If varibles are all declared with an
initializing expression, as above, then any improper reordering
gives a compilation error, due to a variable being undeclared.
It seems to be that separating the declarations and the initial
assignments is more error prone than keeping them together.

> The OP embedded the /logic/ of the program within the declarations.
> That, to me, is /not/ good programming.

I don't understand why you think that. Can you explain further?

> Hope this helps clarify my earlier remarks.

It does help clarify the what. I still don't yet understand the
why.