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  1. str = '[2019-07-29 09:48:11,928] @hr.com [2] [AM] WARN'
  2. p str[/\[[^\]\[]*\].*?\[([^\]\[]*)\]/m, 1]
  3.  
Success #stdin #stdout 0s 6348KB
comments (?)
stdin 
Standard input is empty
stdout 
"2"
https://ideone.com/8SvMKo
language:
Ruby (ruby 2.5.5)
created:
6 years ago
visibility:
secret

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