Quote pattern not matching on *:

[nicolasstucki]

Compiler version

3.4.0

Minimized code

import scala.quoted.*

inline def expandMacro(inline from: Tuple): Any =
  ${ expandMacroImpl }

def expandMacroImpl(using Quotes): Expr[?] =
  '{ 1 *: EmptyTuple } match
    case '{ type t <: Tuple; ($hd: h) *: ($tl: t) } => '{ ??? }
    case x => throw new MatchError(x.show)

def test: Any = expandMacro

Output

-- Error: t/Test2.scala:1:16 ---------------------------------------------------
1 |def test: Any = expandMacro
  |                ^^^^^^^^^^^
  |Exception occurred while executing macro expansion.
  |scala.MatchError: scala.Tuple$package.EmptyTuple.*:[scala.Int, scala.Tuple$package.EmptyTuple.type](1) (of class java.lang.String)
  |     at Test$package$.expandMacroImpl(Test.scala:9)
  |
  |-----------------------------------------------------------------------------
  |Inline stack trace
  |- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
  |This location contains code that was inlined from Test.scala:4
4 |  ${ expandMacroImpl }
  |  ^^^^^^^^^^^^^^^^^^^^
   -----------------------------------------------------------------------------

Expectation

Should match

[nicolasstucki]

Minimization

import scala.quoted.*

inline def expandMacro(inline from: Tuple): Any =
  ${ expandMacroImpl }

def expandMacroImpl(using Quotes): Expr[?] =
  '{ 1 *: EmptyTuple } match
    case '{ ($hd: Int) *: ($tl: Tuple) } => '{ ??? }
    case x => throw new MatchError(x.show)

[nicolasstucki]

The pattern is typed as

case
  '{
    {
      val x$1: Int = ${hd @ _}:Int
      (${tl @ _}:Tuple).*:[Int, Tuple](x$1)
    }
  }
  =>

The val x$1 is probably the cause of this issue.