Allan-Gong

// Reference: http://stackoverflow.com/questions/6803211/whats-the-difference-between-multiple-parameters-lists-and-multiple-parameters

// 1. The multiple arguments lists allow the method to be used in the place of a partially applied function:
object NonCurr {
  def tabulate[A](n: Int, fun: Int => A) = IndexedSeq.tabulate(n)(fun)
}

NonCurr.tabulate[Double](10, _)            // not possible
val x = IndexedSeq.tabulate[Double](10) _  // possible. x is Function1 now
x(math.exp(_))     

Allan-Gong

import com.ning.http.client._
import dispatch._, Defaults._

val requestTimeoutInMs = 5000
val allowSelfSignedSSLCertificate = true

val builder = new AsyncHttpClientConfig.Builder()
builder
  .setAllowPoolingConnections(true)
  .setRequestTimeout(requestTimeoutInMs)

Allan-Gong

// Default way of loading language bundle in Scala Lift
// Relying on language bundle file(s) to be found in src/main/resources/
// LiftRules.resourceNames = List("languageBundle_en_AU")

val appConfDir = System.getProperty("appConfigDirectory")
LiftRules.resourceBundleFactories.prepend {
  case (key, locale) => {
    val file = new File(appConfDir)
    val urls = Array(file.toURI.toURL)
    val loader = new URLClassLoader(urls)

Allan-Gong

  // :*_ tells the compiler to pass each element of arr as its own argument to echo, rather than all of it as a single argument.
  // It is useful when converting list to Map in Scala
  var mutableMapInstanceOfItemToBoolean = scala.collection.mutable.Map(arrayOfSomeSort.values.toList.map(item => item -> false):_*)

Allan-Gong

###################################
#########Encrypt example###########
###################################

use Data::Random qw( rand_chars );
use Crypt::TripleDES;

my $password = q{password};

my $password_len         = length $password;

Allan-Gong

/*******************************/
/***** Implicit conversion *****/
/*******************************/

// If one calls a method m on an object o of a class C, and that class does not support method m, 
// then Scala will look for an implicit conversion from C to something that does support m.

// Use to automatically convert a value from one type to another
val value:BigInt = 1
// What actually happened is:

Allan-Gong

package otherscope {
  class Foo {
  // a method that takes a function and a string, and passes the string into
  // the function, and then executes the function
    def exec(f:(String) => Unit, name: String) {
      f(name)
    }
  }
}

Allan-Gong

sodo yum install perl

sudo yum install bzip2

sudo yum install patch

sudo yum groupinstall 'Development Tools'

\curl -L http://install.perlbrew.pl | bash

Allan-Gong

// cake pattern with self-type annotation

// =======================
// service interfaces
trait OnOffDeviceComponent {
  val onOff: OnOffDevice
  trait OnOffDevice {
    def on: Unit
    def off: Unit
  }

Allan-Gong

// Consider the method tabulate which forms an array from the results of applying a given function f on a range of numbers from 0 until a given length. 
// Up to Scala 2.7, tabulate could be written as follows:

def tabulate[T](len: Int, f: Int => T) = {
    val xs = new Array[T](len)
    for (i <- 0 until len) xs(i) = f(i)
    xs
}

// In Scala 2.8 this is no longer possible, because runtime information is necessary to create the right representation of Array[T].