re = /\{\{ *lang(?:ue)* *\|[^\|\}]*\|(?:[^\}']*''[^\}']*){1,3}\}\}/mi
str = 'oui {{ langue |en|truc\'\' machin \'\'chose\'\'}}
oui {{ langue |en|truc\'\' machin chose}}
oui {{lang| es |truc\'\' machin \'\'chose\'\'}}
oui {{lang| es |truc\'\' machin \'\'chose\'\' \'\'bidule\'\'}}
non {{lang| es |\'\'truc\'\' machin \'\'chose\'\'}}
non {{lien web|langue=es|\'\'truc\'\' machin \'\'chose\'\'}}
non \'\'{{lang| es |truc machin chose}}\'\''
# 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