Overloading constructors isn't special for case classes:
case class Foo(bar: Int, baz: Int) {
def this(bar: Int) = this(bar, 0)
}
new Foo(1, 2)
new Foo(1)
However, you may like to also overload the apply
method in the companion object, which is called when you omit new
.
object Foo {
def apply(bar: Int) = new Foo(bar)
}
Foo(1, 2)
Foo(1)
In Scala 2.8, named and default parameters can often be used instead of overloading.
case class Baz(bar: Int, baz: Int = 0)
new Baz(1)
Baz(1)
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