linear-scala adds support for linear types in Scala via a custom Scalafix linter.
project/plugins.sbt:
addSbtPlugin("com.earldouglas" % "sbt-linear-scala" % "0.0.3")Mix in the Linear interface to prevent values from being
under/over-used.
import com.earldouglas.linearscala.Linear
case class Box(value: Int) extends LinearScalafix finds values that are never used:
trait UnusedField {
val box: Box = Box(42) // error: box is never used
}
trait UnusedParameter {
def foo(x: Box, y: Box): Int = // error: y is never used
x.value
}Scalafix also finds values that are used multiple times:
trait FieldUsedTwice {
val box: Box = Box(42)
println(box) // error: box is used twice
println(box) // error: box is used twice
}See the tests in input/src/main/scala/fix/ for more examples.