scala - Filtering inside for-comprehension with futures -

i doing this:

 (for {     data <- future(getdata)    updated = makechanges(data) if updated != data    _ <- future(saveupdates(updated))    _ <- future(recordtransaction)  } yield ()).recover { case e: nosuchelementexception => () } 

when filter not satisfied, skips remaining 2 steps (good!) throwing exception (not good), have catch , handle @ end. using exceptions flow control not feel elegant me though, wondering if there better way this, aside obvious - wrapping remaining lines if statement:

   _ <- if(updated != data) future(saveupdates(updated)) else future.successful(())    _ <- if(updated != data) ... 

i don't think can avoid exception flow control using comprehension in way, use nested expression instead of filter , handle condition manually giving scala return type needs in case condition not satisfied:

for {   data <- future(data)   updated = makechanges(data)   res = {     if (updated != data) future.successful(())     else {       _ <- future(saveupdates(updated))       _ <- future(recordtransaction)     } yield ()   } } yield res 

but example i'd go simple way , drop comprehension results in more readable code (probably real use case more complex though):

future(data).flatmap(d => {   val updated = makechanges(d)   if(updated == d) future.successful(())   else future(saveupdates(updated)).map(_ => recordtransaction) })