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We have the `# frozen_string_literal: true` comment on all our files. This means all string literals are frozen. There is no need to call #freeze on any literals. For files with `# frozen_string_literal: true` ``` puts %w{a b}[0].frozen? => true puts "hi".frozen? => true puts "a #{1} b".frozen? => true puts ("a " + "b").frozen? => false puts (-("a " + "b")).frozen? => true ``` For more details see: https://samsaffron.com/archive/2018/02/16/reducing-string-duplication-in-ruby
38 lines
853 B
Ruby
38 lines
853 B
Ruby
# frozen_string_literal: true
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# Modified version of: https://github.com/steventen/base62-rb
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module Base62
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KEYS ||= "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
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KEYS_HASH ||= KEYS.each_char.with_index.to_h
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BASE ||= KEYS.length
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# Encodes base10 (decimal) number to base62 string.
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def self.encode(num)
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return "0" if num == 0
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return nil if num < 0
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str = ""
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while num > 0
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# prepend base62 charaters
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str = KEYS[num % BASE] + str
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num = num / BASE
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end
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str
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end
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# Decodes base62 string to a base10 (decimal) number.
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def self.decode(str)
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num = 0
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i = 0
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len = str.length - 1
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# while loop is faster than each_char or other 'idiomatic' way
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while i < str.length
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pow = BASE**(len - i)
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num += KEYS_HASH[str[i]] * pow
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i += 1
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end
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num
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end
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end
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