UserGuide of scalacheck project mentioned sized generators. The explanation code
def matrix[T](g:Gen[T]):Gen[Seq[Seq[T]]] = Gen.sized {size =>
val side = scala.Math.sqrt(size).asInstanceOf[Int] //little change to prevent compile-time exception
Gen.vectorOf(side, Gen.vectorOf(side, g))
}
explained nothing for me. After some exploration I understood that length of generated sequence does not depend on actual size of generator (there is resize method in Gen object that "Creates a resized version of a generator" according to javadoc (maybe that means something different?)).
val g = Gen.choose(1,5)
val g2 = Gen.resize(15, g)
println(matrix(g).sample) // (1)
println(matrix(g2).sample) // (2)
//1,2 produce Seq with same length
Could you explain me what had I missed and give me some examples how you use them in testing code?