scala3 feature examples - macros - inline matches / published by https://github.com/dacr/code-examples-manager #d1f6d051-2dd9-4fbb-bf5a-dc855cd17c47/fb6236c9c1bc5fc308a437448faff2ea48bcfd80

scala3-feature-macro-4-inline-matches.scala

// summary : scala3 feature examples - macros - inline matches
// keywords : scala3, tutorial, macros, inline, meta-programming, @testable
// publish : gist
// authors : David Crosson
// license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2)
// id : d1f6d051-2dd9-4fbb-bf5a-dc855cd17c47
// created-on : 2024-03-17T11:11:11+01:00
// managed-by : https://github.com/dacr/code-examples-manager
// run-with : scala-cli $file

// Inspired from https://docs.scala-lang.org/scala3/guides/macros/inline.html

//> using scala "3.4.0"

import scala.compiletime.error

inline def half(x: Any): Any = {
  inline x match
    case x: Int => x / 2
    case x: String => x.substring(0, x.length / 2)
    case _ => error("Unsupported input data type") // error potentially reported by the compiler
}

@main def go():Unit = {
  println(half(42))
  println(half("The Answer to the Ultimate Question of Life, The Universe, and Everything"))
  println(half('x')) // won't compile
}