Re: Doomsday algorithm

given ($year_anchor_day){
    when(0){@anchorday_week = qw(tuesday wednesday thursday friday sat
+urday
    sunday monday );}
    when(1){@anchorday_week = qw(wednesday thursday friday saturday su
+nday
    monday tuesday);}
    when(2){@anchorday_week=qw(thursday friday saturday sunday monday 
+tuesday
    wednesday);}
    when(3){@anchorday_week=qw(friday saturday sunday monday tuesday w
+ednesday
    thursday);}
    when(4){@anchorday_week=qw(saturday sunday monday tuesday wednesda
+y
    thursday friday);}
    when(5){@anchorday_week=qw(sunday sunday monday tuesday wednesday 
+friday
    saturday);}
    when(6){@anchorday_week = qw(monday tuesday wednesday thursday fri
+day
    saturday sunday);}
}
[download]

This looks ugly to me, and it's not the programmer's task to repeat the same information multiple times.

@anchorday_week = qw(tuesday wednesday thursday friday saturday sunday
+ monday);
my @tmp = splice @anchorday_week, 0, $year_anchor_day;
push @anchorday_week, @tmp;
[download]

(see splice). Probably there are more elegant solutions, but at least it is shorter and won't warn you about given/when …

Update: even simpler: drop that complete @anchorday_week, and then change the calculation of your $nbdays to

my $nbdays = ($diff_to_doomsdates + $year_anchor_day) % 7;
return qw(tuesday wednesday thursday friday saturday sunday monday)[$n
+bdays];
[download]

Comment on Re: Doomsday algorithm Select or Download Code

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Re^2: Doomsday algorithm by QM (Parson) on Sep 07, 2015 at 14:55 UTC
To prove your point, `when(5)` duplicates "sunday". And you probably want something like: `@anchor_day_week = qw(tuesday wednesday thursday friday saturday sunda +y monday) [$year_anchor_day+1..6,0..$year_anchor_day];` [download] ...though I dislike repeating `$year_anchor_day`. This just changes the repetition: `push @anchor_day_week, splice @anchor_day_week, 0, $year_anchor_day;` [download] ...so a function to do this for you would be appropriate, even if it's only used once. -QM -- Quantum Mechanics: The dreams stuff is made of	[reply] [d/l] [select]
Re^3: Doomsday algorithm by soonix (Chancellor) on Sep 07, 2015 at 15:19 UTC
Yes, that's what I meant with "more elegant solution". The next step would be to further "normalize" that `$nbdays` such that Sunday is the usual 0 or 7 (like in strftime %u or %w) by calculating `my $nbdays = ($diff_to_doomsdates + $year_anchor_day + 2) % 7; # or -5` [download]	[reply] [d/l] [select]
Re^2: Doomsday algorithm by QuillMeantTen (Friar) on Sep 08, 2015 at 07:31 UTC
Indeed indeed, its much more elegant to do it that way!	[reply]