re = /:([0-9]{2}[A-Z])(::|:)(.*(?:\r?\n)?(?:(?!:[0-9]{2}[A-Z]:).*(?:\r?\n)?)*)/m
str = ':16R:FIN
:35B:ISIN CH0117044708
ANTEILE -DT USD- SWISSCANTO (CH)
INDEX FUND V - SWISSCANTO (CH)
INDEX EQUITY FUND USA
:16R:FIA
'
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html