Initial commit (9f8bfd71) · Commits · examples / Best Practices in Scala Programming

Best Practices in Scala Programming - Working Files/Chapter 1/No Work Files.rtf

0 → 100755

+7 −0

Changes for Best Practices in Scala Programming - Working Files/Chapter 1/No Work Files.rtf: 7 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		{\rtf1\ansi\ansicpg1252\cocoartf1038\cocoasubrtf350
		{\fonttbl\f0\fswiss\fcharset0 Helvetica;}
		{\colortbl;\red255\green255\blue255;}
		\margl1440\margr1440\vieww9000\viewh8400\viewkind0
		\pard\tx720\tx1440\tx2160\tx2880\tx3600\tx4320\tx5040\tx5760\tx6480\tx7200\tx7920\tx8640\ql\qnatural\pardirnatural

		\f0\fs24 \cf0 No work files for this lesson...}
		No newline at end of file

Best Practices in Scala Programming - Working Files/Chapter 10/AvoidComplexStructuralTyping.scala

0 → 100755

+47 −0

Changes for Best Practices in Scala Programming - Working Files/Chapter 10/AvoidComplexStructuralTyping.scala: 47 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		object AvoidComplexStructuralTyping {

		class Foo(val foo : String) {
		def bar() : String = foo
		}

		def myFunction(input : { def bar() : String }) : String = {
		input.bar().toLowerCase
		}

		def myFunction1(input : { def foo : String }) : String = {
		input.foo.toLowerCase
		}

		def myFunction2(input : { def bar() : String; def foo : String}) : String = {
		input.bar().equals(input.foo).toString
		}

		type NewType = { def bar() : String; def foo : String }

		def myFunction3(input : NewType) : String = {
		input.bar().equals(input.foo).toString
		}

		trait MyTrait {
		def bar() : String
		def foo : String
		}

		def myFunction4(input : MyTrait) : String = {
		input.bar().equals(input.foo).toString
		}

		def myFunction5(input : () => String) : String = {
		input().toLowerCase
		}

		def main(args : Array[String]) : Unit = {
		println(myFunction(new Foo("FoO")))
		println(myFunction1(new Foo("FoO")))
		println(myFunction2(new Foo("FoO")))
		println(myFunction3(new Foo("FoO")))
		println(myFunction4(new Foo("FoO") with MyTrait))
		println(myFunction5(new Foo("FoO").bar))
		}

		}

Best Practices in Scala Programming - Working Files/Chapter 10/AvoidDynamicTyping.scala

0 → 100755

+51 −0

Changes for Best Practices in Scala Programming - Working Files/Chapter 10/AvoidDynamicTyping.scala: 51 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		import scala.language.dynamics

		object AvoidDynamicTyping {

		case class URLCall(url : String, arguments : List[String])

		class Resourcer(val methodMapping : Map[Symbol, URLCall]) extends Dynamic {
		def applyDynamicNamed(name : String)(args : (String, Any)*) = methodMapping.get(Symbol(name)) match {
		case Some(URLCall(url, arguments)) => {
		if(!arguments.equals(args.map(_._1))) {
		throw new IllegalArgumentException(s"Invalid arguments, expected $arguments")
		}
		println(
		args.foldLeft(url)((acc, next) => acc.replaceAll(s":${next._1}", next._2.toString))
		)
		}
		case _ => throw new UnsupportedOperationException(s"Invalid method $name")
		}
		}

		def myFunction() : Unit = {
		val r = new Resourcer(Map(
		'queryGoogle -> URLCall("http://www.google.com/?q=:query", List("query")),
		'getUserById -> URLCall("http://www.foo.bar/user/:id", List("id"))
		))
		r.queryGoogle(query = "foo")
		r.getUserById(id = 1234)
		}

		def myFunction2() : Unit = {
		val r = new Resourcer(Map(
		'getUserById -> URLCall("http://www.foo.bar/user/:id", List("id"))
		))
		try {
		r.queryGoogle(query = "foo")
		} catch {
		case ex : UnsupportedOperationException => ex.printStackTrace()
		}
		try {
		r.getUserById(ID = 1234)
		} catch {
		case ex : IllegalArgumentException => ex.printStackTrace()
		}
		}

		def main(args : Array[String]) : Unit = {
		//myFunction()
		myFunction2()
		}

		}

Best Practices in Scala Programming - Working Files/Chapter 10/AvoidImplicits.scala

0 → 100755

+66 −0

Changes for Best Practices in Scala Programming - Working Files/Chapter 10/AvoidImplicits.scala: 66 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		import java.net.URL

		object AvoidImplicits {

		object Implicits {
		implicit val myFunction1Context : List[String => String] = List(
		x => x.toLowerCase,
		x => x.trim
		)
		implicit val myFunction1Alternate : List[String => String] = List(
		x => x.toUpperCase
		)
		implicit def stringToURL(str : String) : URL = new URL(str)

		implicit class StringToURLable(str : String) {
		def toURL : URL = new URL(str)
		}
		implicit def queryToURL(query : String) : URL = new URL(s"http://www.google.com/?q=$query")
		implicit class QueryParamToURL(str : String) {
		def toGoogleQueryURL : URL = new URL(s"http://www.google.com/?q=$str")
		}
		}

		def myImplicitParams() : Unit = {
		def _myFunction(str : String)(implicit ctx : List[String => String]) : String = {
		ctx.foldLeft(str)((acc, func) => func(acc))
		}
		//println(_myFunction(" FooO "))

		println("[" + _myFunction(" FooO ")(List(_.toLowerCase, _.trim)) + "]")

		import Implicits.myFunction1Context
		println("[" + _myFunction(" FooO ") + "]")
		}

		def myFunction2() : Unit = {
		def _myFunction(obj : URL) : String = {
		obj.getHost
		}
		println(_myFunction(new URL("http://www.google.com")))

		import Implicits.stringToURL
		println(_myFunction("http://www.google.com"))

		import Implicits.StringToURLable
		println(_myFunction("http://www.google.com".toURL))
		}

		def myFunction3() : Unit = {
		def _myFunction(obj : URL) : String = {
		obj.toString
		}
		println(_myFunction(new URL("http://www.google.com/?q=foo")))
		import Implicits.queryToURL
		println(_myFunction("foo"))
		import Implicits.QueryParamToURL
		println(_myFunction("foo".toGoogleQueryURL))
		}

		def main(args : Array[String]) : Unit = {
		//myImplicitParams()
		//myFunction2()
		myFunction3()
		}

		}

Best Practices in Scala Programming - Working Files/Chapter 10/AvoidPostfixNotation.scala

0 → 100755

+32 −0

Changes for Best Practices in Scala Programming - Working Files/Chapter 10/AvoidPostfixNotation.scala: 32 added lines, 0 removed lines.
Original line number	Diff line number	Diff line
		object AvoidPostfixNotation {

		/*def myFunction() : Unit = {
		var length = 0
		val names = List("foo", "bar", "sha", "baz")

		names toList
		length = names.length

		println(length)
		}*/

		def myFunction() : Unit = {
		val names = List("foo", "bar", "sha", "baz")

		names.map {_.toLowerCase}.filter {_.length > 2}

		names map {_.toLowerCase} filter {_.length > 2}
		}

		def myFunction1() : Unit = {
		val names = List("foo", "bar", "sha", "baz")

		names.map(_.toLowerCase).filter(_.length > 2)
		}

		def main(args : Array[String]) : Unit = {
		myFunction()
		myFunction1()
		}

		}