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DarrenN/shortid.rb

Created November 20, 2011 18:02
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Short unique ID (Ruby)
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shortid.rb
t = DateTime
id = t.now.strftime("%Y%m%d%k%M%S%L") # Get current date to the milliseconds
id = id.to_i.to_s(36) # will generate somthing like "5i0sp1h4tkc"
# Reverse it
id.to_i(36)
@robmarable
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Thanks, this is nice!

If you're stuck on 1.8 which doesn't support %L in #strftime, here's a hack that takes advantage of the fact that #to_f returns the millis:

    now_f = Time.now.to_f
    now_i = now_f.to_s.delete('.').to_i
    now_i.to_s(36)

@christhesoul
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Yeah, thanks for this!

I had to change id = t.now.strftime("%Y%m%d%k%M%S%L") to use %H instead of %k as the blank padding in %k was causing issues if somebody did anything before 10am. :)

@Hungor
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Hungor commented Jul 3, 2018

Thanks for this

Based on this, I use the follow line, which I think is more precise due to the addition of sprintf.

id = sprintf("%20.10f", Time.now.to_f).delete('.').to_i.to_s(36)

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