Hoobie

def fibonacci(n: Int): Int =
    if (n == 0) 0
    else if (n == 1) 1
    else fibonacci(n - 1) + fibonacci(n - 2)

@scala.annotation.tailrec
  def tailFibonacci(n: Int, prev: Int = 0, acc: Int = 1): Int =
    if (n == 0) prev
    else if (n == 1) acc
    else tailFibonacci(n - 1, acc, acc + prev)

Hoobie

def factorial(n: Int): Int = if (n > 1) n * factorial(n - 1) else 1

@scala.annotation.tailrec
  def tailFactorial(n: Int, acc: Int = 1): Int =
    if (n == 1) acc
    else tailFactorial(n - 1, n * acc)

Hoobie

A short journey through types in Scala

(based on the Jon Pretty's "Advanced Type Mechanics" workshop)

Type

It is a named collection of method signatures. Those method signatures are called properties.

Classes and traits vs types

We should be careful not to confuse classes or traits and types, because they are different things. Every class and trait gives rise to a type with the same name, but in itself is not a type. Many types also exist which do not solely correspond to a trait or a class.

Hoobie

Terminal tricks

Agenda

1. navigation tricks with cd, pushd, popd
2. some keyboard shortcuts
3. using history as turbo
4. source vs sh
5. running processes in background, nohup

Hoobie

export CLICOLOR=1

PS1="\[\033[0;33m\][\!]\`if [[ \$? = "0" ]]; then echo "\\[\\033[32m\\]"; else echo "\\[\\033[31m\\]"; fi\`[\u.\h: \`if [[ `pwd|wc -c|tr -d " "` > 18 ]]; then echo "\\W"; else echo "\\w"; fi\`]\$\[\033[0m\] "; echo -ne "\033]0;`hostname -s`:`pwd`\007"

Hoobie

package com.example.rx;

import rx.*;

import java.util.Collections;
import java.util.Deque;
import java.util.List;
import java.util.concurrent.ConcurrentLinkedDeque;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;