Discordian date: Difference between revisions

=={{header|Nim}}==

We use a DateTime object as intermediate representation.

<lang Nim>import times, strformat

const

DiscordianOrigin = -1166

SaintTibsDay = "St. Tib’s Day"

type

Season = enum

sCha = (1, "Chaos"), sDis = "Discord", sCon = "Confusion",

sBur = "Bureaucracy", sAft = "The Aftermath"

ErisianWeekDay = enum

eSwe = "Sweetmorn", eBoo = "Boomtime", ePun = "Pungenday",

ePri = "Prickle-Prickle", eSet = "Setting Orange"

SeasonDayRange = range[1..73]

# Description of a discordian date.

DiscordianDate = object

year: int

yearday: YeardayRange

case isSaintTibsDay: bool

of false:

seasondayZero: int

seasonZero: int

weekday: ErisianWeekDay

else:

nil

#---------------------------------------------------------------------------------------------------

proc toDiscordianDate(gdate: DateTime): DiscordianDate =

## Convert a DateTime to a discordian date.

## All the time fields are ignored.

# Create the object.

result = DiscordianDate(isSaintTibsDay: gdate.isLeapDay)

# The yearday field is unchanged.

result.yearday = gdate.yearday

# The year is simply translated.

result.year = gdate.year - DiscordianOrigin

# For remaining fields, we must take in account leap years.

if not result.isSaintTibsDay:

var yearday = result.yearday

if gdate.year.isLeapYear and result.yearday > 59:

dec yearday

# Now, we have simply to use division and modulo using the corrected yearday.

result.seasonZero = yearday div SeasonDayRange.high

result.seasondayZero = yearday mod SeasonDayRange.high

result.weekday = ErisianWeekDay(yearday mod 5)

#---------------------------------------------------------------------------------------------------

proc `$`(date: DiscordianDate): string =

## Convert a discordian date to a string.

if date.isSaintTibsDay:

result = SaintTibsDay

else:

result = fmt"{date.weekday}, {Season(date.seasonZero + 1)} {date.seasondayZero + 1}"

result &= fmt", {date.year} YOLD"

#---------------------------------------------------------------------------------------------------

proc showDiscordianDate(year, month, day: Natural) =

## Show the discordian date corresponding to a gregorian date.

let gdate = initDateTime(year = year, month = Month(month), monthday = day,

hour = 0, minute = 0, second = 0)

echo gdate.format("YYYY-MM-dd"), ": ", $gdate.toDiscordianDate()

#———————————————————————————————————————————————————————————————————————————————————————————————————

showDiscordianDate(2100, 12, 31)

showDiscordianDate(2012, 02, 28)

showDiscordianDate(2012, 02, 29)

showDiscordianDate(2012, 03, 01)

showDiscordianDate(2010, 07, 22)

showDiscordianDate(2012, 09, 02)

showDiscordianDate(2012, 12, 31)</lang>

{{out}}

<pre>2100-12-31: Setting Orange, The Aftermath 73, 3266 YOLD

2012-02-28: Prickle-Prickle, Chaos 59, 3178 YOLD

2012-02-29: St. Tib’s Day, 3178 YOLD

2012-03-01: Setting Orange, Chaos 60, 3178 YOLD

2010-07-22: Pungenday, Confusion 57, 3176 YOLD

2012-09-02: Setting Orange, Bureaucracy 26, 3178 YOLD

2012-12-31: Setting Orange, The Aftermath 73, 3178 YOLD</pre>