re = /https?:\/\/([a-z0-9]+\.)+(at|de|ch)(\/[a-z]+)*\/?(\?[a-z]+=[a-z]*(&[a-z]+=[a-z]*)*)?/
str = 'http://a1.at
http://orf.at/
https://tc.tugraz.at/main
http://www.derstandard.at/kultur/
https://wikipedia.at/wiki/regex/
http://duckduckgo.at/?q=regex
https://gdi.ist.tugraz.at?user=student
http://gdi.ist.tugraz.at/login?course=gdi&role=student
http://tugraz.at?emptyparam=
ε (Leerstring)
http
http://
http://www
http://.at
http://orf.at//
https://de.wikipedia.org
http://tugraz.at/?
http://gdi.ist.tugraz.at/?user=student&
http://?user=student
https://tugraz.at?user'
# 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