scala - Monad transformer for Disjunction and Future -

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i have code returning future[string \/ response], monad instances both disjunction , future , function getresult: response => [string \/ result]. written several nested functions , want see following 

for {   response <- getresponse   result <- getresult(response) } yield result   // future[string \/ result]

as can understand monad transformers using purpose , similar things if had option instead of \/. unfortunately couldn't found futuret nor disjunctiont (although xort exists cats).

so, possible write monad transformer above purpose? may exist or don't understand something.

you can use scalaz.eithert combine effects of \/ (disjunction) , monad, in case future.

def getresponse: future[string \/ response] = ??? def getresult(resp: reponse): future[string \/ result] = ???  (for {   response <- eithert(getresponse)   result <- eithert(getresult(response)) } yield result).run // future[string \/ result]

or change return types of getresponse , getresult functions return eithert :

type r[a] = eithert[future, string, a]  def getresponse: r[response] = ??? def getresult(resp: reponse): r[result] = ???  (for {   response <- getresponse   result <- getresult(response) } yield result).run // future[string \/ result]

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