tenseParser :: Parser (Maybe Tense)
tenseParser = option Nothing 
    $ xmlWrapper "tense" 
    $ Just <$> parserMap [
       ("pres"   , Present)
     , ("imperf" , Imperfect)
     , ("futperf", FuturePerfect)
     , ("fut"    , Future)
     , ("aor"    , Aorist)
     , ("perf"   , Perfect)
     , ("plup"   , Pluperfect)
     ]
tenseParser :: Parser (Maybe Tense)
tenseParser = option Nothing 
    $ xmlWrapper "tense" 
    $ Just <$> parserMap [
       ("pres"   , Present)
     , ("imperf" , Imperfect)
     , ("futperf", FuturePerfect)
     , ("fut"    , Future)
     , ("aor"    , Aorist)
     , ("perf"   , Perfect)
     , ("plup"   , Pluperfect)
     ]
tenseParser = option Nothing 
    $ xmlWrapper "tense" 
    $ Just <$> parserMap [
       ("pres"   , Present)
     , ("imperf" , Imperfect)
     , ("futperf", FuturePerfect)
     , ("fut"    , Future)
     , ("aor"    , Aorist)
     , ("perf"   , Perfect)
     , ("plup"   , Pluperfect)
     ]