Package

prelude

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package prelude

Visibility

Public
All

Type Members

sealed trait Assertion[-A] extends AnyRef
sealed trait AssertionError extends AnyRef
trait Liftables extends AnyRef

Annotations
@silent( ... )
trait QuotedAssertion[A] extends AnyRef
final case class assertionLambdaQuote[A](f: (A) ⇒ Either[AssertionError, Unit]) extends Annotation with StaticAnnotation with Product with Serializable
final case class assertionQuote[A](assertion: Assertion[A]) extends Annotation with StaticAnnotation with Product with Serializable
final case class assertionString(string: String) extends Annotation with StaticAnnotation with Product with Serializable

Value Members

object Assertion

An Assertion[A] is essentially a composable predicate from A => Boolean.
An Assertion[A] is essentially a composable predicate from A => Boolean. They can be composed with standard Boolean operators of &&, || and !. This is primarily intended to be used with Newtype and Subtype, enhancing them with compile-time time validation.
For example, if you'd like to validate that a particular Int is precisely 4 digits long, you can create the following refined Newtype. (Note that the syntax is slightly difference between Scala 2 and Scala 3).
```
type Pin = Pin.Type
object Pin extends Newtype[Int] {
  // Scala 2 Syntax
  def assertion =
    assert(Assertion.between(1000, 9999))

  // Scala 3 Syntax
  override inline def assertion =
    Assertion.between(1000, 9999)
}

// PowerOfTwo(1000) compiles
// PowerOfTwo(5412) compiles
// PowerOfTwo(34567) fails with "34567 did not satisfy between(1000, 9999)"
// PowerOfTwo(234) fails with "123 did not satisfy between(1000, 9999)"
```
object AssertionError
package macros

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