re = /^(?=.*status[:=](\S+)|)(?=.*type[:=](\S+)|)(?:.*?title[:=])?(?|"([^"\n]+)"|((?:(?!\s?(?:type|status)).)+))[^"\n]*$/m
str = 'stack overflow
"stackoverflow"
title="stack overflow"
type:image title=stack overflow
stackoverflow type:image
status:closed type:image title:stack overflow
title="stack overflow" type:joy
title:you should totally drop regex and try jquery type:joke'
subst = ''
result = str.gsub(re, subst)
# Print the result of the substitution
puts result
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