Scala Programming Projects

Strict val

The following is a strict variable declaration:

class StrictDemo {
  val strictVal = {
    println("Evaluating strictVal")
    "Hello"
  }
}
val strictDemo = new StrictDemo
//Evaluating strictVal
//strictDemo: StrictDemo = StrictDemo@32fac009

We can see that println is called immediately. This means that the block at the right side of the assignment is evaluated as soon as the StrictDemo class is instantiated. If we want to delay the block's evaluation, we have to use the lazy prefix.