hashids.rb

# cf. https://html-preview.github.io/?url=https://github.com/hashids/hashids.github.io/blob/master/index.html
require "hashids"

puts "Default alphabet length: #{Hashids::DEFAULT_ALPHABET.length}"

hashids = Hashids.new("This is salt", 10)
puts <<MSG
Alphabet: #{hashids.alphabet}
Alphabet length: #{hashids.alphabet.length}
Seps: #{hashids.seps}
Guards: #{hashids.guards}

Number | ID | ID without padding or lottery | Lottery
-------|----|--------------------|---------
MSG
(1..8).each do |power|
  base = hashids.alphabet.length ** power
  [-1, 0].each do |delta|
    n = base + delta
    id = hashids.encode(n)
    parts = id.tr(hashids.guards, " ").split(" ")
    id_without_pad = parts.size == 1 ? parts[0] : parts[1]
    lottery = id_without_pad.slice!(0)
    puts [n, id, id_without_pad, lottery].join(" | ")
  end
end

Default alphabet length: 62
Alphabet: xaX6zvqDORgL9NPw42AnlmWk8JrG1o0bQBEVpdKe53yM
Alphabet length: 44
Seps: iIfHhcUSCFustT
Guards: 7ZYj

Number	ID	ID without padding or lottery	Lottery
43	oOE7MJZ8MN	J	M
44	5Ge7xnEYq6	nE	x
1935	me9ZVxxjEq	xx	V
1936	8X7pyOOZQz	yOO	p
85183	8V7e000jkn	000	e
85184	BdZ5y666ZA	y666	5
3748095	lRjDDDDDjz	DDDD	D
3748096	njOW9999j3	W9999	O
164916223	4Ykyyyyy7D	yyyyy	k
164916224	y78Dqqqqq7	Dqqqqq	8
7256313855	KjLkkkkkkY	kkkkkk	L
7256313856	Z9yOOOOOOZ	yOOOOOO	9
319277809663	ZnvvvvvvvZ	vvvvvvv	n
319277809664	7lKOOOOOOO	KOOOOOOO	l
14048223625215	Ywkkkkkkkk	kkkkkkkk	w
14048223625216	4X99999999	X99999999	4