Softsapiens

  trait Serialiser[A]{
    def toJson(x: A): String
  }

  // [A: Serialiser] means the compiler expects an implicit Serialiser 
  // needs to be available for A
  def writeJsonToDisk[A: Serialiser](item: A){
    def writeToDisk(x:String){println(s"I saved [$x] to disk, honest!")}
    
    // Access the parameter with implicity

Softsapiens

import shapeless._
import ops.record.{ Selector, Updater }
import record.{ FieldType, field }

trait PathLens[T, P] {
  type Elem
  def get(t : T) : Elem
  def set(t : T)(e : Elem) : T
}

Softsapiens

miles@frege:~$ scala
Welcome to Scala version 2.11.0 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_55).
Type in expressions to have them evaluated.
Type :help for more information.

scala> import scala.language.dynamics
import scala.language.dynamics

scala> case class Assoc[K, V](value: V)
defined class Assoc

Softsapiens

#!/usr/bin/env scalas

/***
// $ cs sbt/sbt --branch 0.13.2b
// $ export CONSCRIPT_OPTS="-XX:MaxPermSize=512M -Dfile.encoding=UTF-8"
// $ chmod -x scripts.scala
scalaVersion := "2.10.4"

resolvers += Resolver.url("typesafe-ivy-repo", url("http://typesafe.artifactoryonline.com/typesafe/releases"))(Resolver.ivyStylePatterns)

Softsapiens

import scala.concurrent.{ ExecutionContext, Future }
import shapeless._, ops.tuple.{ IsComposite, LeftFolder, Prepend }

object zipAndAdd extends Poly2 {
  implicit def only[B, A](implicit p: Prepend[B, Tuple1[A]], executor: ExecutionContext) =
    at[Future[B], Future[A]] {
      (fb, fa) => fb.zip(fa).map { case (b, a) => p(b, Tuple1(a)) }
    }
}

Softsapiens

#!/bin/bash

#########################################################################################################################
# MIT License
#  
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
# INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Softsapiens

import java.io.{ FileOutputStream, File }
import scala.io.Source
import scala.util.matching.Regex

object UpdateCopyrightHeaders extends App {
  val encoding = "utf-8"
  val copyrightLines: Seq[String] = "Copyright (C) 1894-2014 Example Corp. <http://www.example.com>".split("\n")
  val srcDir = new File("src/")

  def updateCopyright(file: File): Unit = {

Softsapiens

#!/usr/bin/env zsh

# in fino veritas
 
# Borrowing shamelessly from these oh-my-zsh themes:
#   fino-time
#   pure
#   https://gist.github.com/smileart/3750104

# Set required options

Softsapiens

miles@frege:~$ scala
Welcome to Scala version 2.11.0 (Java HotSpot(TM) 64-Bit Server VM, Java 1.7.0_55).
Type in expressions to have them evaluated.
Type :help for more information.

scala> import scala.language.dynamics
import scala.language.dynamics

scala> case class Assoc[K, V](value: V)
defined class Assoc

Softsapiens

/** GADTs in Scala and their limitations */

/** Background: what is an algebraic data type (ADT) ? 
  * ADT: (possibly) recursive datatype with sums and products
  * In scala - a trait with case classes (case class is product, subtyping is sum) 
  */

/** Motivation: untyped embedded DSL doesn't prevent nonsensical expressions */
sealed trait Expr { 
  def apply(other: Expr) = Ap(this, other)