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  1. a = []
  2. puts "\n2 hel2 lo".enum_for(:scan, /(?<![^[:space:]])2([[:space:].)])/).map{Regexp.last_match.begin(0)}
  3. puts "\n2 hel2 lo".enum_for(:scan, /(?<=\s|^)2\s/).map{Regexp.last_match.begin(0)}
Success #stdin #stdout 0.01s 28688KB
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https://ideone.com/NxIhwe
language:
Ruby (ruby 2.5.5)
created:
8 years ago
visibility:
public

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