jdegoes

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

noelmarkham

import...	What it imports
cats.std.type	Typeclass instances for standard library type (think List, Option)
cats.syntax.type	“Enhanced” methods for type (.toRightXor etc)
cats.data.type	Imports a type not part of the standard library (think Xor, Kleisli) and its typeclass instances

frosforever

scalacOptions ++= Seq(
//  "-Xprint:typer", // Turn this on if WartRemover acts up, to see full syntax tree
  "-deprecation",
  "-encoding", "UTF-8",       // yes, this is 2 args
  "-feature",
  "-unchecked",
  "-Xfatal-warnings",       // Treat Warnings as Errors
  "-Xlint",
  "-Yno-adapted-args",
  "-Ywarn-dead-code",        // N.B. doesn't work well with the ??? hole

cvogt

// Please comment in case of typos or bugs
 
import scala.slick.driver.H2Driver._
val db = Database.for...(...)

case class Record( ... )
class Records(tag: Tag) extends Table[Record](tag,"RECORDS"){
  ...
  def * = ... <> (Record.tupled,Record.unapply)
  // place additional methods here which return values of type Column