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Iterate over arbitrary-length tuple

I just started with Scala and ran into a problem:

Scala has the Types Tuple1, Tuple2, …, Tuple22. Scalaquery returns tuples when iterating over queries.

I have now a given class (ZK’s ListitemRenderer), which accepts Objects and populates gui lists with rows, each consisting of some cells. But ListitemRenderer isn’t generic. So my problem is that i have an Object “data”, which really is a tuple of arbitrary length, which i have to iterate over to create the cells (simply with data._1.toString, …).

Since there is no I didn’t know the supertype to Tuple1-22, i can’t couldn’t just do data.asInstanceOf[Tuple].produc开发者_JAVA百科tIterator foreach {…}

What can i do?


Below Answer told me that there is indeed a Trait to all Tuples – Product – providing the desired foreach function.


All TupleX classes inherit from Product, which defines def productIterator : Iterator[Any]. You can call it to iterates through all elements of any tuple.

For example:

def toStringSeq(tuple: Product) = tuple.productIterator.map(_.toString).toIndexedSeq
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