list,scala,foreach,scala-collections , Compare each element of Scala list against rest of elements in the list

## Question:

Tag: list,scala,foreach,scala-collections

I have a list of Custom objects which will be compared against rest of the objects in the same list.

My current approach: Currently i take one element from a the list using foreach loop,run another foreach loop to look through the list for elements that are similar to the taken object.

``````case class TestOb(name:String,pos:Vector[Int])

val lis:List[TestOb] = null

lis.foreach{i=>
val ref = i._2
lis.foreach{j=>
val current = j._2
//compare ref and current.
}
}
``````

Is there any other efficient way to do this iteration in Scala within same list without having two foreach loops?

Have you tried using the `for`-loop?

``````for( a <- lis; b <- lis) {
// do stuff with a and b
}
``````

For further convinience here an easy example to get an idea of the iteration going on behind the scenes:

``````scala> val list = 1 to 3
list: scala.collection.immutable.Range.Inclusive = Range(1, 2, 3)
scala> for(a <- list; b <- list) println(a+" - "+b)
1 - 1
1 - 2
1 - 3
2 - 1
2 - 2
2 - 3
3 - 1
3 - 2
3 - 3
``````

For what its worth, enzymes solution would be more in line with the functional style scala embraces.

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