re = /^(\[(No|S\d( Act \d)?|Lore) Spoilers\])?[^\[\]\n]+$/m
str = '[No Spoilers] Here\'s The Title
[S2 Act 2 Spoilers] Here\'s The Title
[S2 Act 7 Spoilers] Here\'s The Title
[S7 Act 7 Spoilers] Here\'s The Title
Here\'s The Title
Here\'s The Title [No Spoilers]
[Invalid Spoilers] Here\'s The Title'
# 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