Best practice for use constants in scala annotations

Question

I use tapestry 5 as my choice of web framework. Tapestry allows me to define symbols in the configure class and inject symbols into other components.

for example,

Answer 1

The 'final' keyword is required to make the compiler emit it as you would do it in Java. E.g.,

object Foo
{
   final val MY_SYMBOLIC_CONSTANT="whatever"
}

It seems that, otherwise, you only get an accessor method under the hood which is not statically calculable.

Answer 2

It doesn't seem possible w/ scala versions 2.8.1.final, 2.8.2.final, or 2.9.1.final (the result was the same with all):

object Constant { val UNCHECKED = "unchecked" }

class Test {                                       
    @SuppressWarnings(Array(Constant.UNCHECKED))   
    def test: Unit = println("testing.. 1, 2... 3")
}

.

<console>:7: error: annotation argument needs to be a constant; found: Constant.UNCHECKED
           @SuppressWarnings(Array(Constant.UNCHECKED))