Gmatch is a tiny matcher of google-like query patterns, called "goopat"s: gm = Gmatch( "color: blue - sky size: < 100" ) if gm.match( record ): ... matching_records = [rec for rec in records if gm.match( rec )] A "record" is a dict, or namedtuple, or Dotdict, or anything with record.get( key ) -> value. A "goopat" pattern is made up of the following elements, here with examples: color: a key or field name, followed by a ":" colon blu words made of letters and numbers match anywhere in a field, case-insensitive: blu matches Blue Blur sublunar blue sky match all the words, anywhere in a field, in any order: bluesky sky-blue "frisky ... blues" blue - sky blue but not sky -- put blanks around the "-" blue green - sky cloud blue and green but not sky and not cloud Double quotes are used for: "key.word", "http://a-b-c.net" names containing special characters "sky blue" sky, any amount of white space, then blue " sky blue " an exact word or phrase, not e.g. "frisky blues" r"regular expression" see http://docs.python.org/library/re.html . Gmatch compiles them with re.I case-insensitive and re.X, ignore white space except "\ " and "[ ]" ; Comparing: size: < <= > >= == != compare record.get( "size" ) to a number or string size: < 100 here size must be a number, or a string like "12.3" size: >= "Large" here it must be a string (beware: "Small" > "Large"). size: >= 100 < 200 matches sizes in the range 100 to 200. Notes, ramblings, corner cases ... (REs are pretty fast, ~ 20 Mbytes/sec on my mac ppc with python 2.5.1 .) Download files, 2feb -- 246 gmatch.py http://denis.pastebin.com/m6609dea0 154 gmparse.py http://denis.pastebin.com/m308ba33b