Scala: building bridges between programming domains
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The document discusses Scala's capabilities in various programming domains, highlighting features like expressions, case classes, pattern matching, and higher-order functions. It also covers bridges to functional, concurrent, and distributed programming, along with Scala's application in big data, web development, and systems programming. The text references various Scala functionality and provides code snippets illustrating these concepts.
![Parameterized types
class List[+A]
class Set[A]
class Function1[-A, +B]
type T1 = List[Number]
type T2 = Set[String]
type T3 = Function1[String, Int]
Based on https://www.slideshare.net/Odersky/scala-the-simple-parts (slide 47)](https://image.slidesharecdn.com/scalabuildingbridgesbetweenprogrammingdomains-190502232153/85/Scala-building-bridges-between-programming-domains-8-320.jpg)
(implicit ord: Order[A]): A =
if (ord.lteqv(x, y)) x else y
min(2, 3) // 2
min("abc", "xyz") // "abc"
min(List(3, 8, 5), List(2, 7, 9)) // List(2, 7, 9)
Based on https://www.slideshare.net/Odersky/scala-the-simple-parts (slide 49)](https://image.slidesharecdn.com/scalabuildingbridgesbetweenprogrammingdomains-190502232153/85/Scala-building-bridges-between-programming-domains-9-320.jpg)
![Higher-kinded types
trait Functor[F[_]]
trait Applicative[F[_]]
trait Monad[F[_]]
type T1 = Functor[Option]
type T2 = Applicative[ValidatedA]
type T3 = Monad[List]](https://image.slidesharecdn.com/scalabuildingbridgesbetweenprogrammingdomains-190502232153/85/Scala-building-bridges-between-programming-domains-10-320.jpg)
![Stream.resource(blockingExecutionContext).flatMap { blockingEC =>
io.file
.readAll[IO](Paths.get("fahrenheit.txt"), blockingEC, 4096)
.through(text.utf8Decode).through(text.lines)
.filter(s => !s.trim.isEmpty && !s.startsWith("//"))
.map(line => fahrenheitToCelsius(line.toDouble).toString)
.intersperse("n")
.through(text.utf8Encode)
.through(io.file.writeAll(Paths.get("celsius.txt"), blockingEC))
}.compile.drain.unsafeRunSync()
Bridge to concurrent and distributed programming
https://github.com/functional-streams-for-scala/fs2/blob/series/1.0/docs/ReadmeExample.md](https://image.slidesharecdn.com/scalabuildingbridgesbetweenprogrammingdomains-190502232153/85/Scala-building-bridges-between-programming-domains-17-320.jpg)
![Bridge to systems programming
type Vec = CStruct3[Double, Double, Double]
val vec = stackalloc[Vec] // allocate c struct on stack
!vec._1 = 10.0 // initialize fields
!vec._2 = 20.0
!vec._3 = 30.0
length(vec) // pass by reference
http://www.scala-native.org](https://image.slidesharecdn.com/scalabuildingbridgesbetweenprogrammingdomains-190502232153/85/Scala-building-bridges-between-programming-domains-26-320.jpg)
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