re = /DTS.?(HD|ES|X(?!\D))|TRUEHD|ATMOS|DD(\+|P).?([5-9])|EAC3.?([5-9])/m
str = '#DTS matches
DTSHD
DTSES
DTSX5
DTS5HD
#DTS non-matches
DTSXXX
DTSA
#these two are just exact matches
TRUEHD
ATMOS
#they are found anywhere in the text
ATMOSPHERE
#DD matches
DD+5
DD+$5 #here $ is matched by .?
DD+45
DDP5
#DD non-matches
DD
DDA
DD+4
DDPx4
#EAC matches
EAC345
EAC35
#EAC non-matches
EAC34
'
# 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