Fix doc and add regression test

Author: nicolasstucki

docs/docs/reference/metaprogramming/macros.md

@@ -618,7 +618,7 @@ In case all files are suspended due to cyclic dependencies the compilation will
 
 It is possible to deconstruct or extract values out of `Expr` using pattern matching.
 
-#### scala.quoted .matching
+#### scala.quoted.matching
 
 In `scala.quoted.matching` contains object that can help extract values from `Expr`.
 
@@ -661,19 +661,19 @@ optimize {
 
 ```scala
 def sum(args: =>Int*): Int = args.sum
-def optimize(arg: Int): Int = ${ optimizeExpr('arg) }
-def optimizeExpr(body: Expr[Int])(given QuoteContext): Expr[Int] = body match {
+inline def optimize(arg: Int): Int = ${ optimizeExpr('arg) }
+private def optimizeExpr(body: Expr[Int])(given QuoteContext): Expr[Int] = body match {
   // Match a call to sum without any arguments
   case '{ sum() } => Expr(0)
   // Match a call to sum with an argument $n of type Int. n will be the Expr[Int] representing the argument.
   case '{ sum($n) } => n
   // Match a call to sum and extracts all its args in an `Expr[Seq[Int]]`
-  case '{ sum($args: _*) } => sumExpr(args)
+  case '{ sum(${ExprSeq(args)}: _*) } => sumExpr(args)
   case body => body
 }
-def sumExpr(args: Expr[Seq[Int]])(given QuoteContext): Expr[Int] = args.underlyingArgument match {
+private def sumExpr(args1: Seq[Expr[Int]])(given QuoteContext): Expr[Int] = {
     def flatSumArgs(arg: Expr[Int]): Seq[Expr[Int]] = arg match {
-      case '{ sum($subArgs: _*) } => subArgs.flatMap(listflatSumArgsSum)
+      case '{ sum(${ExprSeq(subArgs)}: _*) } => subArgs.flatMap(flatSumArgs)
       case arg => Seq(arg)
     }
     val args2 = args1.flatMap(flatSumArgs)

tests/run-macros/quoted-matching-docs-2.check

@@ -0,0 +1,6 @@
+6
+6
+12.+(Test.a)
+17
+4.+(Macro_1$package.sum((Test.seq: scala.<repeated>[scala.Int])))
+13

tests/run-macros/quoted-matching-docs-2/Macro_1.scala

@@ -0,0 +1,37 @@
+import scala.quoted._
+import scala.quoted.matching._
+
+def sum(args: =>Int*): Int = args.sum
+
+inline def showOptimize(arg: Int): String = ${ showOptimizeExpr('arg) }
+inline def optimize(arg: Int): Int = ${ optimizeExpr('arg) }
+
+private def showOptimizeExpr(body: Expr[Int])(given QuoteContext): Expr[String] =
+  Expr(optimizeExpr(body).show)
+
+private def optimizeExpr(body: Expr[Int])(given QuoteContext): Expr[Int] = body match {
+  // Match a call to sum without any arguments
+  case '{ sum() } => Expr(0)
+  // Match a call to sum with an argument $n of type Int. n will be the Expr[Int] representing the argument.
+  case '{ sum($n) } => n
+  // Match a call to sum and extracts all its args in an `Expr[Seq[Int]]`
+  case '{ sum(${ExprSeq(args)}: _*) } => sumExpr(args)
+  case body => body
+}
+
+private def sumExpr(args1: Seq[Expr[Int]])(given QuoteContext): Expr[Int] = {
+    def flatSumArgs(arg: Expr[Int]): Seq[Expr[Int]] = arg match {
+      case '{ sum(${ExprSeq(subArgs)}: _*) } => subArgs.flatMap(flatSumArgs)
+      case arg => Seq(arg)
+    }
+    val args2 = args1.flatMap(flatSumArgs)
+    val staticSum: Int = args2.map {
+      case Const(arg) => arg
+      case _ => 0
+    }.sum
+    val dynamicSum: Seq[Expr[Int]] = args2.filter {
+      case Const(_) => false
+      case arg => true
+    }
+    dynamicSum.foldLeft(Expr(staticSum))((acc, arg) => '{ $acc + $arg })
+}

tests/run-macros/quoted-matching-docs-2/Test_2.scala

@@ -0,0 +1,10 @@
+object Test extends App {
+  println(showOptimize(sum(1, 2, 3)))
+  println(optimize(sum(1, 2, 3)))
+  val a: Int = 5
+  println(showOptimize(sum(1, a, sum(1, 2, 3), 5)))
+  println(optimize(sum(1, a, sum(1, 2, 3), 5)))
+  val seq: Seq[Int] = Seq(1, 3, 5)
+  println(showOptimize(sum(1, sum(seq: _*), 3)))
+  println(optimize(sum(1, sum(seq: _*), 3)))
+}