xuwei-k

import scala.compiletime.ops.string.Length
import scala.compiletime.ops.string.CharAt
import scala.compiletime.ops.string.Substring
import scala.compiletime.ops.int
import scala.compiletime.ops.long
import scala.language.dynamics

object Witness extends Dynamic {
  type StringTail[A <: String] = Substring[A, 1, Length[A]]

xuwei-k

import play.api.BuiltInComponents
import play.api.Mode
import play.api.mvc._
import play.api.routing._
import play.api.routing.sird._
import play.core.server.PekkoHttpServer
import play.core.server.ServerConfig

object Main {
  // 1つのScalaファイルで済むので、

xuwei-k

Welcome to Scala 2.12.18 (OpenJDK 64-Bit Server VM, Java 11.0.20).
Type in expressions for evaluation. Or try :help.

scala> val <a>{ b }</a> = <a></a>
scala.MatchError: <a></a> (of class scala.xml.Elem)
  ... 55 elided

scala> val <a>{ _ }</a> = <a>c</a>

scala> val <a>{ _* }</a> = <a>c</a>

xuwei-k

package p1

import org.openjdk.jmh.annotations.Benchmark

object Bench {
  val values: List[Either[Int, Int]] = (1 to 100_000).map{
    case n if n % 2 == 0 =>
      Right(n)
    case n =>
      Left(n)

xuwei-k

  public java.lang.String x(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=2, args_size=2
         0: aload_1
         1: invokedynamic #27,  0             // InvokeDynamic #0:makeConcatWithConstants:(Ljava/lang/String;)Ljava/lang/String;
         6: areturn

xuwei-k

package example

trait Functor[F[_]] {
  def map[A, B](fa: F[A])(f: A => B): F[B]
}

object Functor {
  def fromPolyFunction[F[_]](x: [A, B] => (fa: F[A]) => (f: A => B) => F[B]): Functor[F] =
    new Functor[F] {
      def map[A, B](fa: F[A])(f: A => B): F[B] = x(fa)(f)

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scalaVersion := "3.3.0"

libraryDependencies += "org.openjdk.jol" % "jol-core" % "0.17"

xuwei-k

import play.api.BuiltInComponents
import play.api.Mode
import play.api.mvc._
import play.api.routing._
import play.api.routing.sird._
import play.core.server.NettyServer
import play.core.server.ServerConfig

object Main {
  // 1つのScalaファイルで済むので、

xuwei-k

package a {
  object X

  package b {
    object Y
  }
}

package b {
  object Z

xuwei-k

    # checkoutその他は省略
    - run: sbt compileなどの他のタスク色々 writeExternalDependencies
    - name: upload dependencies.txt
      if: github.event_name == 'push'
      run: |
        # いい感じにuploadとdownloadできれば、
        # github actionsのartifactでもなんでも良い。
        # 最近某所ではS3の方が便利というか楽なので、それ使ったりもしているので、その場合の例
        aws s3 cp target/dependencies.txt s3://適当なURI/${{github.ref_name}}/dependencies.txt
    - id: get_previous_dependencies