N'th

(Spurious apostrophes intentionally omitted.)

my %irregulars = <1 st 2 nd 3 rd>, (11..13 X=> 'th');

sub nth ($n) { $n ~ ( %irregulars{$n % 100} // %irregulars{$n % 10} // 'th' ) }

say .list».&nth for [^26], [250..265], [1000..1025];

Output:

0th 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th 12th 13th 14th 15th 16th 17th 18th 19th 20th 21st 22nd 23rd 24th 25th
250th 251st 252nd 253rd 254th 255th 256th 257th 258th 259th 260th 261st 262nd 263rd 264th 265th
1000th 1001st 1002nd 1003rd 1004th 1005th 1006th 1007th 1008th 1009th 1010th 1011th 1012th 1013th 1014th 1015th 1016th 1017th 1018th 1019th 1020th 1021st 1022nd 1023rd 1024th 1025th

If you want to get Unicodally fancy, use this version instead:

my %irregulars = <1 ˢᵗ 2 ⁿᵈ 3 ʳᵈ>, (11..13 X=> 'ᵗʰ');

sub nth ($n) { $n ~ ( %irregulars{$n % 100} // %irregulars{$n % 10} // 'ᵗʰ' ) }

say .list».&nth for [^26], [250..265], [1000..1025];

250ᵗʰ 251ˢᵗ 252ⁿᵈ 253ʳᵈ 254ᵗʰ 255ᵗʰ 256ᵗʰ 257ᵗʰ 258ᵗʰ 259ᵗʰ 260ᵗʰ 261ˢᵗ 262ⁿᵈ 263ʳᵈ 264ᵗʰ 265ᵗʰ