Last active
May 27, 2023 06:29
-
-
Save dacr/8db8b1273bbcee1173cf39e1936b3080 to your computer and use it in GitHub Desktop.
Collection operations / published by https://github.com/dacr/code-examples-manager #3783b8e4-99a6-44b4-b106-d06cd5646a96/e217a26895cc4f9d14400653e982c0c8ec023f9f
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
// summary : Collection operations | |
// keywords : scala, scalatest, collection, cheatsheet, @testable | |
// publish : gist | |
// authors : David Crosson | |
// license : Apache NON-AI License Version 2.0 (https://raw.githubusercontent.com/non-ai-licenses/non-ai-licenses/main/NON-AI-APACHE2) | |
// id : 3783b8e4-99a6-44b4-b106-d06cd5646a96 | |
// created-on : 2021-03-04T20:00:03Z | |
// managed-by : https://github.com/dacr/code-examples-manager | |
// run-with : scala-cli $file | |
// --------------------- | |
//> using scala "3.3.0" | |
//> using dep "org.scalatest::scalatest:3.2.16" | |
//> using objectWrapper | |
// --------------------- | |
import java.text.spi.DecimalFormatSymbolsProvider | |
import java.text.{DecimalFormat, DecimalFormatSymbols, NumberFormat} | |
import org.scalatest._ | |
import flatspec._ | |
import matchers._ | |
class CollectionOperations extends AnyFlatSpec with should.Matchers { | |
override def suiteName="CollectionOperations" | |
// --------------------------------------------------------------------------------------------- | |
"A collection" should "support safe get by index with lift" in { | |
Array(42).lift(0) shouldBe Some(42) | |
Array(42).lift(42) shouldBe None | |
Array(42).lift(-42) shouldBe None | |
List("a","b","c").lift(2) shouldBe Some("c") | |
List("a","b","c").lift(42) shouldBe None | |
List("a","b","c").lift(-42) shouldBe None | |
} | |
// --------------------------------------------------------------------------------------------- | |
it should "replace any kind of loop without any constraint" in { | |
info("iterator .iterate advantageously .from method as it fully generic") | |
LazyList | |
.iterate(10L)(_ + 1) | |
.zip(Iterator.iterate(0L)(_ + 1)) | |
.takeWhile{ case(value, index) => index < 5} | |
.map{ case (value, index)=>value} | |
.sum shouldBe 10+11+12+13+14 | |
} | |
// --------------------------------------------------------------------------------------------- | |
} | |
org.scalatest.tools.Runner.main(Array("-oDF", "-s", classOf[CollectionOperations].getName)) |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment