How do I declare a generic variable in Scala without initializing it (or initializing to any value)?
def foo[T] {
var t: T = ???? // tried _, null
t
}
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2 Answers
def foo[T] {
var t: T = null.asInstanceOf[T]
t
}
And, if you don't like the ceremony involved in that, you can ease it this way:
// Import this into your scope
case class Init()
implicit def initToT[T](i: Init): T = {
null.asInstanceOf[T]
}
// Then use it
def foo[T] {
var t: T = Init()
t
}
Comments
You can't not initialize local variables, but you can do so for fields:
scala> class foo[T] {
| var t: T = _
| }
defined class foo
answered Oct 19, 2009 at 21:07
Daniel C. Sobral
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1 Comment
IttayD
do you know why it is allowed for class variables but not method variables?