Play scala functions return multiple items multiple times

Question

I have a function that returns Long and a Json object which I would like to call multiple times using the same variable names.

def returnMultipleItems (): (Long, JsObject) = {

    val number:Long = 123

    val json = Json.obj(
        "Name" -> "Tom",
        "age" -> 42
    )

    return(number, json)
}

When calling the function like this it works fine.

var (number, json) = returnMultipleItems    
println("Number = " + number, ", Json = " + json)

I would like to call the function two or more times using the same variable names. With this I get error messages like ";" is expected but "=" is found.

var number:Long = 0
var json:JsObject = Json.obj()

(number, json) = returnMultipleItems // Call the function

(number, json) = returnMultipleItems // Call the function again

score 1 · Answer 1 · edited May 23 '17 at 11:49

1

Scala does not accept multiple variable assigment. However, your first example works because Scala interprets the form var (x, y) = (1, 2) as pattern matching.

A full explanation is here and workarounds are here.

edited May 23 '17 at 11:49

Community

1
1

answered Mar 17 '14 at 23:49

Rafa Paez

4,820
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score 1 · Accepted Answer · answered Mar 17 '14 at 23:51

May not be exactly what you're looking for but you could assign the variable to the tuple (instead of the contents) e.g.

var numJson = returnMultipleItems
println("Number = " + numJson._1, ", Json = " + numJson._2)
numJson = returnMultipleItems
println("Number = " + numJson._1, ", Json = " + numJson._2)

Play scala functions return multiple items multiple times

2 Answers2