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advanced_named_captures

🧩 Compose parsers with Regexp named captures​

Ruby’s named captures (?<name>) let you extract complex data in one pattern. You can nest or chain patterns and then retrieve results via MatchData#named_captures for clean, self‑documenting code. This works wonders in DSL interpreters or log parsing.

pattern = /
  \A(?<date>\d{4}-\d{2}-\d{2})\s+
  \[(?<level>INFO|ERROR)\]\s+
  (?<msg>.+)
\z/x
line = "2024-07-01 [ERROR] Disk full"
md = pattern.match(line)
puts md.named_captures
# => {"date"=>"2024-07-01", "level"=>"ERROR", "msg"=>"Disk full"}