xuwei-k

$ scala -Xprint:typer -e "for { a <- Option(2) ; b <- Option(a) } yield b"
[[syntax trees at end of                     typer]] // scalacmd15102494186904250690.scala
package <empty> {
  object Main extends scala.AnyRef {
    def <init>(): Main.type = {
      Main.super.<init>();
      ()
    };
    def main(args: Array[String]): Unit = {
      final class $anon extends scala.AnyRef {

xuwei-k

package example

import org.wartremover.WartTraverser
import org.wartremover.WartUniverse

object DisableDoobieReadInstance extends WartTraverser {
  override def apply(u: WartUniverse): u.Traverser =
    new u.Traverser(this) {
      import q.reflect.*
      override def traverseTree(tree: Tree)(owner: Symbol): Unit = {

xuwei-k

import scala.quoted.*

object Foo {
  inline def f[A](inline x: A): List[(String, String)] = ${ impl('x) }

  def impl[A](using q: Quotes)(x: Expr[A]): Expr[List[(String, String)]] = {
    import q.reflect.*
    x.asTerm match {
      case Inlined(_, _, Block(_, Match(_, i :: Nil))) =>
        i match {

xuwei-k

TaskKey[Seq[String]]("allMainClassNames") := Def.taskDyn {
  buildStructure.value.units
    .apply(Keys.thisProjectRef.value.build)
    .defined
    .values
    .toList
    .map { p =>
      LocalProject(p.id) / Compile / discoveredMainClasses
    }
    .join

xuwei-k

package example

import scodec.bits.*
import scodec.codecs.*

object Main {

  val iterations = 1000000000

  val str = "Hello World!"

xuwei-k

• https://github.com/xuwei-k/quote-pattern-match-benchmark/commit/cdc390533ac457810fd5ed93ea59f35d1033b450

[info] Benchmark                 Mode  Cnt  Score   Error  Units
[info] Main.hasTypeVariable     thrpt   10  0.051 ± 0.002  ops/s
[info] Main.lowLevelReflection  thrpt   10  0.361 ± 0.010  ops/s
[info] Main.noTypeVariable      thrpt   10  0.223 ± 0.004  ops/s

xuwei-k

• 6.543094 Null
• 5.654039 MapUnit
• 4.128198 SeqApply
• 1.990676 StringPlusAny
• 1.58011 AutoUnboxing
• 1.447845 IterableOps
• 1.424732 PlatformDefault
• 1.257947 Equals
• 1.251545 Overloading
• 0.813279 RedundantIsInstanceOf

xuwei-k

• ImplicitParameter 1.065469
• Overloading 0.510683
• Null 0.334346
• AutoUnboxing 0.280608
• ListAppend 0.24645
• IterableOps 0.130154
• SortFilter 0.107256
• Recursion 0.102776
• Any 0.100167
• AsInstanceOf 0.060164

xuwei-k

xuwei-k

package fix

import scala.meta.Defn
import scala.meta.Term
import scala.meta.transversers.*
import scalafix.Patch
import scalafix.lint.Diagnostic
import scalafix.lint.LintSeverity
import scalafix.v1.SyntacticDocument
import scalafix.v1.SyntacticRule