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

bfritz

andypiper

The basics

This is a collection of basic "recipes", many using twurl (the Swiss Army Knife for the Twitter API!) and jq to query the Twitter API and format the results. Also, some scripts to test or automate common actions.

deanwampler

{
  "metadata" : {
    "name" : "GraphFramesExample",
    "user_save_timestamp" : "1970-01-01T01:00:00.000Z",
    "auto_save_timestamp" : "1970-01-01T01:00:00.000Z",
    "language_info" : {
      "name" : "scala",
      "file_extension" : "scala",
      "codemirror_mode" : "text/x-scala"
    },

rjsvaljean

package com.xdotai

import shapeless._
import shapeless.ops.hlist.{Prepend, Align, Remove}

object TypedPipelineComposition {

  import ShapelessExt._

cvogt

// a List isn't a Map
scala> val x: Map[Int,Int] = List(1,2,3).map(i => i -> i)
<console>:16: error: type mismatch;
 found   : List[(Int, Int)]
 required: Map[Int,Int]
       val x: Map[Int,Int] = List(1,2,3).map(i => i -> i)
                                            ^
// first create List, then create Map. Intermediate collection overhead
scala> val x: Map[Int,Int] = List(1,2,3).map(i => i -> i).toMap 
x: Map[Int,Int] = Map(1 -> 1, 2 -> 2, 3 -> 3)

andershammar

#!/bin/bash -ex

if [ "$(cat /mnt/var/lib/info/instance.json | jq -r .isMaster)" == "true" ]; then
    # Install Git
    sudo yum -y install git

    # Install Maven
    wget -P /tmp http://apache.mirrors.spacedump.net/maven/maven-3/3.3.3/binaries/apache-maven-3.3.3-bin.tar.gz
    sudo mkdir /opt/apache-maven
    sudo tar -xvzf /tmp/apache-maven-3.3.3-bin.tar.gz -C /opt/apache-maven

klenwell

#
# This playbook assumes the WebSphere MQ file provided by IBM has already been
# downloaded to a specific directory (target.wd) on the server. 
#
# ${target.wd} is a variable representing the working directory on the target
# server the MQ client will be installed.
#
# Note: Although this playbook is designed to be able to be run independently,
# it is in fact part of a longer playbook and therefore may have some other
# unexpected dependencies not reflected here.

chids

package inception.commands;

import static org.junit.Assert.assertArrayEquals;
import static org.junit.Assert.assertEquals;

import javax.ws.rs.client.Entity;

import org.mockito.ArgumentMatcher;

public class UnfuckEntity extends ArgumentMatcher<Entity<?>> {

m4rw3r

use std::fmt;
use std::ascii::StrAsciiExt;

#[deriving(Clone,Eq)]
pub enum HeaderName {
	Accept,
	AcceptCharset,
	AcceptEncoding,
	AcceptLanguage,
	Age,