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dacr/scala-basics.sc

Last active May 25, 2024 10:20
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  1. dacr revised this gist May 25, 2024. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    @@ -9,7 +9,7 @@
    // run-with : scala-cli $file

    // ---------------------
    //> using scala "3.4.2"
    //> using scala "3.4.2"
    //> using dep "org.scalatest::scalatest:3.2.16"
    //> using objectWrapper
    // ---------------------
  2. dacr revised this gist May 25, 2024. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    @@ -9,7 +9,7 @@
    // run-with : scala-cli $file

    // ---------------------
    //> using scala "3.3.0"
    //> using scala "3.4.2"
    //> using dep "org.scalatest::scalatest:3.2.16"
    //> using objectWrapper
    // ---------------------
  3. dacr revised this gist May 27, 2023. 1 changed file with 3 additions and 2 deletions.
    5 changes: 3 additions & 2 deletions scala-basics.sc
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    @@ -9,8 +9,9 @@
    // run-with : scala-cli $file

    // ---------------------
    //> using scala "3.1.1"
    //> using dep "org.scalatest::scalatest:3.2.10"
    //> using scala "3.3.0"
    //> using dep "org.scalatest::scalatest:3.2.16"
    //> using objectWrapper
    // ---------------------

    import org.scalatest._, wordspec._, matchers._, OptionValues._
  4. dacr revised this gist Apr 2, 2023. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions scala-basics.sc
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    @@ -2,15 +2,15 @@
    // keywords : scala, learning, @testable
    // publish : gist
    // authors : David Crosson
    // license : Apache2 BUT Machine Learning models training is not allowed by the author
    // license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2)
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // managed-by : https://github.com/dacr/code-examples-manager
    // run-with : scala-cli $file

    // ---------------------
    //> using scala "3.1.1"
    //> using lib "org.scalatest::scalatest:3.2.10"
    //> using dep "org.scalatest::scalatest:3.2.10"
    // ---------------------

    import org.scalatest._, wordspec._, matchers._, OptionValues._
  5. dacr revised this gist Dec 11, 2022. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -2,7 +2,7 @@
    // keywords : scala, learning, @testable
    // publish : gist
    // authors : David Crosson
    // license : Apache2
    // license : Apache2 BUT Machine Learning models training is not allowed by the author
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // managed-by : https://github.com/dacr/code-examples-manager
  6. dacr revised this gist Jul 20, 2022. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -6,7 +6,7 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // managed-by : https://github.com/dacr/code-examples-manager
    // run-with : scala-cli $scriptFile
    // run-with : scala-cli $file

    // ---------------------
    //> using scala "3.1.1"
  7. dacr revised this gist Jan 28, 2022. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions scala-basics.sc
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    @@ -9,8 +9,8 @@
    // run-with : scala-cli $scriptFile

    // ---------------------
    // using scala 3.1.0
    // using lib "org.scalatest::scalatest:3.2.10"
    //> using scala "3.1.1"
    //> using lib "org.scalatest::scalatest:3.2.10"
    // ---------------------

    import org.scalatest._, wordspec._, matchers._, OptionValues._
  8. dacr revised this gist Dec 18, 2021. 1 changed file with 6 additions and 6 deletions.
    12 changes: 6 additions & 6 deletions scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -38,9 +38,10 @@ class ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    list.tail shouldBe List(1, 3, 1, 5, 2, 2)
    list.last shouldBe 2
    intercept[Exception] {
    List.empty[Int].lastOption shouldBe None
    List.empty[Int].last shouldBe 1
    }
    List.empty[Int].lastOption shouldBe None
    List.empty[Int].lastOption shouldBe None
    list.init shouldBe List(4, 1, 3, 1, 5, 2)
    list.take(2) shouldBe List(4, 1)
    list.drop(4) shouldBe List(5, 2, 2)
    @@ -113,8 +114,8 @@ class ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    Array(1, 2, 3) === Array(1, 2, 3L) shouldBe true
    Array(1, 2, Array(3, 4)) === Array(1, 2, Array(3, 4)) shouldBe true
    Array(1, 2, List(3, 4)) === Array(1, 2, List(3, 5)) shouldBe false
    Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5)) shouldBe true // ???
    Array(1, 2, Array(3, 4)) !== Array(1, 2, Array(3, 5)) shouldBe true
    (Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5))) shouldBe true // ???
    (Array(1, 2, Array(3, 4)) !== Array(1, 2, Array(3, 5))) shouldBe true
    }
    }
    // ===================================================
    @@ -142,9 +143,8 @@ class ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    """line1
    |line2""".stripMargin
    "line1\nline2" should be equals res
    //"line1\nline2" shouldEqual res // Strange it doesn't work
    info("Take care with be and references !")
    "line1\nline2" should not be(res) // --- Take care so !! be != equals
    "line1\nline2" shouldEqual res
    String("line1\nline2") should be(res)
    }
    // -------------------------------------------------
    "support basic string interpolations" in {
  9. dacr revised this gist Nov 30, 2021. 1 changed file with 7 additions and 3 deletions.
    10 changes: 7 additions & 3 deletions scala-basics.sc
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    @@ -6,9 +6,13 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // managed-by : https://github.com/dacr/code-examples-manager
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'
    // run-with : scala-cli $scriptFile

    // ---------------------
    // using scala 3.1.0
    // using lib "org.scalatest::scalatest:3.2.10"
    // ---------------------

    import $ivy.`org.scalatest::scalatest:3.2.6`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale

    @@ -34,7 +38,7 @@ class ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    list.tail shouldBe List(1, 3, 1, 5, 2, 2)
    list.last shouldBe 2
    intercept[Exception] {
    List.empty[Int].last shouldBe None
    List.empty[Int].lastOption shouldBe None
    }
    List.empty[Int].lastOption shouldBe None
    list.init shouldBe List(4, 1, 3, 1, 5, 2)
  10. dacr revised this gist Nov 30, 2021. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions scala-basics.sc
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    @@ -5,6 +5,7 @@
    // license : Apache2
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // managed-by : https://github.com/dacr/code-examples-manager
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.2.6`
  11. dacr revised this gist Nov 29, 2021. 1 changed file with 1 addition and 0 deletions.
    1 change: 1 addition & 0 deletions scala-basics.sc
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    @@ -4,6 +4,7 @@
    // authors : David Crosson
    // license : Apache2
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // created-on : 2020-05-31T19:54:52Z
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.2.6`
  12. dacr revised this gist Mar 27, 2021. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -6,7 +6,7 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.2.5`
    import $ivy.`org.scalatest::scalatest:3.2.6`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale

  13. dacr revised this gist Mar 7, 2021. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -6,7 +6,7 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.2.2`
    import $ivy.`org.scalatest::scalatest:3.2.5`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale

  14. dacr revised this gist Oct 9, 2020. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    @@ -2,7 +2,7 @@
    // keywords : scala, learning, @testable
    // publish : gist
    // authors : David Crosson
    // license : GPL
    // license : Apache2
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

  15. dacr revised this gist Oct 3, 2020. No changes.
  16. dacr revised this gist Sep 8, 2020. 1 changed file with 2 additions and 2 deletions.
    4 changes: 2 additions & 2 deletions scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -10,7 +10,7 @@ import $ivy.`org.scalatest::scalatest:3.2.2`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale

    object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    class ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    override def suiteName: String = "Scala Language Basics"

    "scala language" must {
    @@ -206,4 +206,4 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    }


    ScalaLanguageBasicsTest.execute()
    org.scalatest.tools.Runner.main(Array("-oDF", "-s", classOf[ScalaLanguageBasicsTest].getName))
  17. dacr revised this gist Sep 6, 2020. 1 changed file with 0 additions and 58 deletions.
    58 changes: 0 additions & 58 deletions scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -9,8 +9,6 @@
    import $ivy.`org.scalatest::scalatest:3.2.2`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale
    import scala.concurrent.Future
    import scala.util.Success

    object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    override def suiteName: String = "Scala Language Basics"
    @@ -208,60 +206,4 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    }


    object ScalaLanguageAsyncBasicsTest extends AsyncWordSpec with should.Matchers {
    override def suiteName: String = "Scala Language Asynchronous Basics"

    "Scala language" must {
    // ===================================================
    "Futures" can {
    "be created" in {
    Future{
    1
    }.map{result => result shouldBe 1}
    }
    // -------------------------------------------------
    "be badly composed" in {
    def f1() = Future{1}
    def f2() = Future{2}
    val futureResult = for {
    r1 <- f1()
    r2 <- f2() // will start only once f1 has finished
    } yield r1+r2
    futureResult.map{_ shouldBe 3}
    }
    // -------------------------------------------------
    "be better composed" in {
    val f1 = Future{1}
    val f2 = Future{2}
    val futureResult = for {
    r1 <- f1
    r2 <- f2
    } yield r1+r2
    futureResult.map{_ shouldBe 3}
    }
    // -------------------------------------------------
    "be reduced" in {
    val futures: Seq[Future[Int]] = Seq(Future{1}, Future{2})
    val future: Future[Seq[Int]] = Future.sequence(futures)
    future.map(_.sum shouldBe 3)
    }
    // -------------------------------------------------
    "transparent operation" in {
    Future{"A"}
    .andThen{case Success(value) => value+"B" }
    .map{_ shouldBe "A"}
    }
    // -------------------------------------------------
    "recover from failure" in {
    Future{throw new Exception("BAD")}
    .recover{ th => "A" }
    .map{_ shouldBe "A"}
    }
    }
    // ===================================================
    }
    }


    ScalaLanguageBasicsTest.execute()
    ScalaLanguageAsyncBasicsTest.execute()
  18. dacr revised this gist Sep 4, 2020. 1 changed file with 1 addition and 1 deletion.
    2 changes: 1 addition & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -6,7 +6,7 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.2.0`
    import $ivy.`org.scalatest::scalatest:3.2.2`
    import org.scalatest._, wordspec._, matchers._, OptionValues._
    import java.util.Locale
    import scala.concurrent.Future
  19. dacr revised this gist Jul 7, 2020. 1 changed file with 2 additions and 1 deletion.
    3 changes: 2 additions & 1 deletion scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -1,7 +1,8 @@
    // summary : scala language
    // keywords : scala, learning, @testable
    // publish : gist, snippet
    // publish : gist
    // authors : David Crosson
    // license : GPL
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

  20. dacr revised this gist Jun 30, 2020. 1 changed file with 17 additions and 1 deletion.
    18 changes: 17 additions & 1 deletion scala-basics.sc
    View file
    Original file line number Diff line number Diff line change
    @@ -108,7 +108,7 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    Array(1, 2, 3) === Array(1, 2, 3L) shouldBe true
    Array(1, 2, Array(3, 4)) === Array(1, 2, Array(3, 4)) shouldBe true
    Array(1, 2, List(3, 4)) === Array(1, 2, List(3, 5)) shouldBe false
    Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5)) shouldBe true
    Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5)) shouldBe true // ???
    Array(1, 2, Array(3, 4)) !== Array(1, 2, Array(3, 5)) shouldBe true
    }
    }
    @@ -187,6 +187,22 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    }
    }
    // ===================================================
    "Currying" can {
    "support in lambda" in {
    val f = (x:Int) => (y:Int) => (z:Int) => x+y+z
    // -------------
    f(1)
    f(1)(2)
    f(1)(2)(3)
    }
    "support in function" in {
    def f(x:Int)(y:Int)(z:Int):Int = x+y+z
    // -------------
    f(1)(_:Int)(_:Int) // mandatory at lest up to scala 2.13
    f(1)(2)(_)
    f(1)(2)(3)
    }
    }
    }
    }

  21. dacr revised this gist Jun 26, 2020. 1 changed file with 14 additions and 5 deletions.
    19 changes: 14 additions & 5 deletions scala-basics.sc
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    Original file line number Diff line number Diff line change
    @@ -5,9 +5,9 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.1.1`
    import $ivy.`org.scalatest::scalatest:3.2.0`
    import org.scalatest._, wordspec._, matchers._, OptionValues._

    import java.util.Locale
    import scala.concurrent.Future
    import scala.util.Success

    @@ -101,9 +101,13 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    Array(1, 2, 3) == Array(1, 2, 3) shouldBe true
    }
    info("But with the triple equal, === it is correctly checked")
    List(1, 2, 3) === List(1, 2, 3)
    List(1, 2, 3) === List(1, 2, 3) shouldBe true
    List(1, 2, 3) === List(1, 2, 4) shouldBe false
    Array(1, 2, 3) === Array(1, 2, 3) shouldBe true
    Array(1, 2, 3) === Array(1, 2, 4) shouldBe false
    Array(1, 2, 3) === Array(1, 2, 3L) shouldBe true
    Array(1, 2, Array(3, 4)) === Array(1, 2, Array(3, 4)) shouldBe true
    Array(1, 2, List(3, 4)) === Array(1, 2, List(3, 5)) shouldBe false
    Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5)) shouldBe true
    Array(1, 2, Array(3, 4)) !== Array(1, 2, Array(3, 5)) shouldBe true
    }
    @@ -129,9 +133,13 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    // -------------------------------------------------
    "be defined using multiple lines" in {
    info("With stripMargin method you can even keep the right code indentation")
    "line1\nline2" shouldBe
    val res =
    """line1
    |line2""".stripMargin
    "line1\nline2" should be equals res
    //"line1\nline2" shouldEqual res // Strange it doesn't work
    info("Take care with be and references !")
    "line1\nline2" should not be(res) // --- Take care so !! be != equals
    }
    // -------------------------------------------------
    "support basic string interpolations" in {
    @@ -147,8 +155,9 @@ object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    }
    // -------------------------------------------------
    "support basic printf like interpolations with locale changes" in {
    Locale.setDefault(Locale.US) // TODO - find better alternative
    val price = 32.54351
    f"The price is $price%.1f" shouldBe "The price is 032.5 dollar"
    f"The price is $price%.1f dollar" shouldBe "The price is 32.5 dollar"
    }
    // -------------------------------------------------
    "support basic raw strings" in {
  22. dacr revised this gist Apr 23, 2020. 1 changed file with 4 additions and 4 deletions.
    8 changes: 4 additions & 4 deletions scala-basics.sc
    View file
    Original file line number Diff line number Diff line change
    @@ -5,13 +5,13 @@
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.0.8`
    import org.scalatest._
    import $ivy.`org.scalatest::scalatest:3.1.1`
    import org.scalatest._, wordspec._, matchers._, OptionValues._

    import scala.concurrent.Future
    import scala.util.Success

    object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    object ScalaLanguageBasicsTest extends AnyWordSpec with should.Matchers {
    override def suiteName: String = "Scala Language Basics"

    "scala language" must {
    @@ -182,7 +182,7 @@ object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    }


    object ScalaLanguageAsyncBasicsTest extends AsyncWordSpec with Matchers {
    object ScalaLanguageAsyncBasicsTest extends AsyncWordSpec with should.Matchers {
    override def suiteName: String = "Scala Language Asynchronous Basics"

    "Scala language" must {
  23. dacr revised this gist Nov 30, 2019. 1 changed file with 162 additions and 20 deletions.
    182 changes: 162 additions & 20 deletions scala-basics.sc
    View file
    Original file line number Diff line number Diff line change
    @@ -8,9 +8,13 @@
    import $ivy.`org.scalatest::scalatest:3.0.8`
    import org.scalatest._

    import scala.concurrent.Future
    import scala.util.Success

    object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    override def suiteName: String = "Language Basics"
    "scala" must {
    override def suiteName: String = "Scala Language Basics"

    "scala language" must {
    // ===================================================
    "List" can {
    // -------------------------------------------------
    @@ -19,35 +23,95 @@ object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    }
    // -------------------------------------------------
    "be initialized" in {
    List(1,2,3,4).size shouldBe 4
    List(1, 2, 3, 4).size shouldBe 4
    }
    // -------------------------------------------------
    "provide a set of standard useful operations" in {
    val list = List(4, 1, 3, 1, 5, 2, 2 )
    val list = List(4, 1, 3, 1, 5, 2, 2)
    list.size shouldBe 7
    list.distinct shouldBe List(4, 1, 3, 5, 2)
    list.sorted shouldBe List(1, 1, 2, 2, 3, 4, 5)
    list.head shouldBe 4
    list.tail shouldBe List(1, 3, 1, 5, 2, 2 )
    list.init shouldBe List(4, 1, 3, 1, 5, 2 )
    list.tail shouldBe List(1, 3, 1, 5, 2, 2)
    list.last shouldBe 2
    intercept[Exception] {
    List.empty[Int].last shouldBe None
    }
    List.empty[Int].lastOption shouldBe None
    list.init shouldBe List(4, 1, 3, 1, 5, 2)
    list.take(2) shouldBe List(4, 1)
    list.drop(4) shouldBe List(5, 2, 2)
    list.reverse shouldBe List(2,2,5,1,3,1,4)
    list.distinct shouldBe List(4, 1, 3, 5, 2)
    list.sorted shouldBe List(1, 1, 2, 2, 3, 4, 5)
    list.reverse shouldBe List(2, 2, 5, 1, 3, 1, 4)
    }
    // -------------------------------------------------
    "be filtered, queried and checked" in {
    val list = List(4, 1, 3, 1, 5, 2, 2)
    list.exists(_ == 5) shouldBe true
    list.count(_ % 3 == 0) shouldBe 1
    list.contains(5) shouldBe true
    list.find(_ == 3) shouldBe Some(3)
    list.find(_ == 42) shouldBe None
    list.filter(_ < 3) shouldBe List(1, 1, 2, 2)
    list.filterNot(_ == 2) shouldBe List(4, 1, 3, 1, 5)
    list.forall(_ % 2 == 0) shouldBe false
    list.min shouldBe 1
    list.max shouldBe 5
    list.sum shouldBe 18
    list.reduce(_ + _) shouldBe 18
    intercept[Exception] {
    List.empty[Int].min shouldBe 0
    }
    List.empty[Int].minOption shouldBe None
    List.empty[Int].maxOption shouldBe None
    List.empty[Int].sum shouldBe 0
    }
    // -------------------------------------------------
    "be transformed" in {
    val list = List(4, 1, 3, 1, 5, 2, 2)
    list.map(_ + 1) shouldBe List(5, 2, 4, 2, 6, 3, 3)
    }
    // -------------------------------------------------
    "comparable each other" in {
    List(1, 2, 3) == List(1, 2, 3) shouldBe true
    List(1, 2, 3) != List(1, 2, 4) shouldBe true
    List(1, 2, List(3, 4)) == List(1, 2, List(3, 4)) shouldBe true
    List(1, 2, List(3, 4)) != List(1, 2, List(3, 5)) shouldBe true
    }
    // -------------------------------------------------
    "be map/reduce" in {
    List(1,2,3,4,5,6,7,8,9,10,11,12)
    .filter(_ % 2 == 0)
    .map(_ + 1d)
    .reduce(_ + _) shouldBe 48d
    }
    }
    // ===================================================
    "Arrays" can {
    info("Arrays are collections as any others")
    info("Arrays are collections as any others but with some issues...")
    info("There's no dedicated syntax")
    // -------------------------------------------------
    "be created in a simple way" in {
    Array(1,2,3)
    Array(1, 2, 3)
    }
    // -------------------------------------------------
    "have some issues unfortunately with equalities" in {
    info("All collection are deeply compared, but arrays have issues")
    List(1, 2, 3) == List(1, 2, 3) shouldBe true
    intercept[Exception] {
    Array(1, 2, 3) == Array(1, 2, 3) shouldBe true
    }
    info("But with the triple equal, === it is correctly checked")
    List(1, 2, 3) === List(1, 2, 3)
    Array(1, 2, 3) === Array(1, 2, 3) shouldBe true
    Array(1, 2, Array(3, 4)) === Array(1, 2, Array(3, 4)) shouldBe true
    Array(1, 2, List(3, 4)) !== Array(1, 2, List(3, 5)) shouldBe true
    Array(1, 2, Array(3, 4)) !== Array(1, 2, Array(3, 5)) shouldBe true
    }
    }
    // ===================================================
    "Strings" can {
    "Strings" can {
    // -------------------------------------------------
    "provide usefull utilities methods" in {
    "provide useful utilities methods" in {
    "TRUC".toLowerCase shouldBe "truc"
    "truc".toUpperCase shouldBe "TRUC"
    "truc".capitalize shouldBe "Truc"
    @@ -56,7 +120,7 @@ object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    "truc".startsWith("tr") shouldBe true
    "truc".equalsIgnoreCase("TRUC") shouldBe true
    "truc".matches(".*uc") shouldBe true
    "1 2 3".split(" ") shouldBe Array("1","2","3")
    "1 2 3".split(" ") shouldBe Array("1", "2", "3")
    }
    // -------------------------------------------------
    "equals and == are the same" in {
    @@ -71,29 +135,107 @@ object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    }
    // -------------------------------------------------
    "support basic string interpolations" in {
    val age=32
    val age = 32
    s"Sarah is $age years old" shouldBe "Sarah is 32 years old"
    s"Sarah is ${age+1} years old" shouldBe "Sarah is 33 years old"
    s"Sarah is ${age + 1} years old" shouldBe "Sarah is 33 years old"
    }
    // -------------------------------------------------
    "support basic printf like interpolations" in {
    val name="joe"
    val name = "joe"
    f"[$name%7s]" shouldBe "[ joe]"
    f"[$name%-7s]" shouldBe "[joe ]"
    }
    // -------------------------------------------------
    "support basic printf like interpolations with locale changes" in {
    val price=32.54351
    val price = 32.54351
    f"The price is $price%.1f" shouldBe "The price is 032.5 dollar"
    }
    // -------------------------------------------------
    "support basic raw strings" in {
    val x=2
    val x = 2
    raw"x=$x\nsameline" shouldBe """x=2\nsameline"""
    raw"x=$x\nsameline" shouldBe "x=2\\nsameline"
    }
    }
    // ===================================================
    "Regexps" can {
    // -------------------------------------------------
    "match strings" in {
    val reg = "(?i)john .*".r
    ("John Doe" match {case reg() => true}) shouldBe true
    reg.matches("John Doe") shouldBe true
    }
    // -------------------------------------------------
    "extract sub string" in {
    val reg = """(?i)john\s+(.*)""".r
    ("John Doe" match {case reg(lastName) => lastName}) shouldBe "Doe"
    }
    // -------------------------------------------------
    "extract sub strings" in {
    val reg = """(?i)john\s+(.*)""".r
    List("john Doe", "john chose")
    .collect{case reg(lastName)=>lastName} shouldBe List("Doe", "chose")
    }
    }
    // ===================================================
    }
    }


    object ScalaLanguageAsyncBasicsTest extends AsyncWordSpec with Matchers {
    override def suiteName: String = "Scala Language Asynchronous Basics"

    "Scala language" must {
    // ===================================================
    "Futures" can {
    "be created" in {
    Future{
    1
    }.map{result => result shouldBe 1}
    }
    // -------------------------------------------------
    "be badly composed" in {
    def f1() = Future{1}
    def f2() = Future{2}
    val futureResult = for {
    r1 <- f1()
    r2 <- f2() // will start only once f1 has finished
    } yield r1+r2
    futureResult.map{_ shouldBe 3}
    }
    // -------------------------------------------------
    "be better composed" in {
    val f1 = Future{1}
    val f2 = Future{2}
    val futureResult = for {
    r1 <- f1
    r2 <- f2
    } yield r1+r2
    futureResult.map{_ shouldBe 3}
    }
    // -------------------------------------------------
    "be reduced" in {
    val futures: Seq[Future[Int]] = Seq(Future{1}, Future{2})
    val future: Future[Seq[Int]] = Future.sequence(futures)
    future.map(_.sum shouldBe 3)
    }
    // -------------------------------------------------
    "transparent operation" in {
    Future{"A"}
    .andThen{case Success(value) => value+"B" }
    .map{_ shouldBe "A"}
    }
    // -------------------------------------------------
    "recover from failure" in {
    Future{throw new Exception("BAD")}
    .recover{ th => "A" }
    .map{_ shouldBe "A"}
    }
    }
    // ===================================================
    }
    }

    ScalaLanguageBasicsTest.execute()

    ScalaLanguageBasicsTest.execute()
    ScalaLanguageAsyncBasicsTest.execute()
  24. dacr created this gist Oct 29, 2019.
    99 changes: 99 additions & 0 deletions scala-basics.sc
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,99 @@
    // summary : scala language
    // keywords : scala, learning, @testable
    // publish : gist, snippet
    // authors : David Crosson
    // id : 84200162-6102-4e5c-9ade-19296bc405f8
    // execution : scala ammonite script (http://ammonite.io/) - run as follow 'amm scriptname.sc'

    import $ivy.`org.scalatest::scalatest:3.0.8`
    import org.scalatest._

    object ScalaLanguageBasicsTest extends WordSpec with Matchers {
    override def suiteName: String = "Language Basics"
    "scala" must {
    // ===================================================
    "List" can {
    // -------------------------------------------------
    "be empty" in {
    List().isEmpty shouldBe true
    }
    // -------------------------------------------------
    "be initialized" in {
    List(1,2,3,4).size shouldBe 4
    }
    // -------------------------------------------------
    "provide a set of standard useful operations" in {
    val list = List(4, 1, 3, 1, 5, 2, 2 )
    list.size shouldBe 7
    list.distinct shouldBe List(4, 1, 3, 5, 2)
    list.sorted shouldBe List(1, 1, 2, 2, 3, 4, 5)
    list.head shouldBe 4
    list.tail shouldBe List(1, 3, 1, 5, 2, 2 )
    list.init shouldBe List(4, 1, 3, 1, 5, 2 )
    list.take(2) shouldBe List(4, 1)
    list.drop(4) shouldBe List(5, 2, 2)
    list.reverse shouldBe List(2,2,5,1,3,1,4)
    }
    }
    // ===================================================
    "Arrays" can {
    info("Arrays are collections as any others")
    info("There's no dedicated syntax")
    // -------------------------------------------------
    "be created in a simple way" in {
    Array(1,2,3)
    }
    }
    // ===================================================
    "Strings" can {
    // -------------------------------------------------
    "provide usefull utilities methods" in {
    "TRUC".toLowerCase shouldBe "truc"
    "truc".toUpperCase shouldBe "TRUC"
    "truc".capitalize shouldBe "Truc"
    "truc".endsWith("uc") shouldBe true
    "truc".contains("ru") shouldBe true
    "truc".startsWith("tr") shouldBe true
    "truc".equalsIgnoreCase("TRUC") shouldBe true
    "truc".matches(".*uc") shouldBe true
    "1 2 3".split(" ") shouldBe Array("1","2","3")
    }
    // -------------------------------------------------
    "equals and == are the same" in {
    ("truc" == new String("truc")) shouldBe true
    }
    // -------------------------------------------------
    "be defined using multiple lines" in {
    info("With stripMargin method you can even keep the right code indentation")
    "line1\nline2" shouldBe
    """line1
    |line2""".stripMargin
    }
    // -------------------------------------------------
    "support basic string interpolations" in {
    val age=32
    s"Sarah is $age years old" shouldBe "Sarah is 32 years old"
    s"Sarah is ${age+1} years old" shouldBe "Sarah is 33 years old"
    }
    // -------------------------------------------------
    "support basic printf like interpolations" in {
    val name="joe"
    f"[$name%7s]" shouldBe "[ joe]"
    f"[$name%-7s]" shouldBe "[joe ]"
    }
    // -------------------------------------------------
    "support basic printf like interpolations with locale changes" in {
    val price=32.54351
    f"The price is $price%.1f" shouldBe "The price is 032.5 dollar"
    }
    // -------------------------------------------------
    "support basic raw strings" in {
    val x=2
    raw"x=$x\nsameline" shouldBe """x=2\nsameline"""
    raw"x=$x\nsameline" shouldBe "x=2\\nsameline"
    }
    }
    }
    }

    ScalaLanguageBasicsTest.execute()