Use yield with if

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3

Just adding to @crater2150’s suggestions…

I’d consider applying the filtering at the Data level. This would also provide a better API for passing the predicate as an argument instead of hardwiring a single filter, e.g.

def readCsvDatabase(
    filename: String,
    pred: Data => Boolean = Function.const(true)
): List[Data] =
  ???

…to be called as

readCsvDatabase("data/data.csv")

or

readCsvDatabase("data/data.csv", _.isValid == 1)

I’d also apply conversion to Data and subsequent filtering while still on the iterator, before converting to a collection. This way, in the filtering case you’ll only need to fit the filtered result items in memory rather than the full unfiltered result. Further, as there is no dependency on the result from previous computations, no flatMap/for expression is actually required…

def parseLine(line: String): Data = ???

bufferedSource
  .getLines()
  .drop(1)
  .map(parseLine)
  .filter(pred)
  .toList

Finally, the source should be closed after use - consider Using or similar to ensure this.

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