JEG2

ElixirConf Training Sneak Peek

I've done a practice run of one fourth of my ElixirConf training. It was very helpful to me and I would like a little more practice.

I plan to run sessons for one half of my training next week. The sessions will be:

• Tuesday at 7:00 PM Central Time: Process Basics
• Wednesday at 7:00 PM Central Time: "Special Processes"

Each session is planned to last about an hour and a half.

JEG2

module ARandomNumberASecond exposing (main)

import Html exposing (..)
import Html.App
import Time exposing (Time, second)
import Random


type alias Flags = {randSeed : Int}

JEG2

defmodule PubSubServer do
  def start(subscriber_callback \\ nil) do
    spawn(__MODULE__, :run, [[ ], subscriber_callback])
  end

  def subscribe(server, handler) do
    send(server, {:subscribe, self})
    listen(handler)
  end

JEG2

require "open-uri"
require "json"
require "benchmark"

REPO_URL = "https://api.github.com/users/JEG2/repos"

def github_api(url)
  open(url) { |response| JSON.parse(response.read) }
end

JEG2

>> class Magic
>>   def initialize
>>     self.var = 42
>>     puts var
>>   end
>>   attr_accessor :var
>> end
=> nil
>> Magic.new
42

JEG2

>> s = "active_model/errors"
=> "active_model/errors"
>> i = 0
=> 0
>> while (md = s.match(/(?:_|(\/))([a-z\d]*)/i, i)); s[md.begin(0)...md.end(0)] = "#{md[1]}#{md[2].capitalize}"; i = md.end(0) - 1 end
=> nil
>> s
=> "activeModel/Errors"

JEG2

require "minitest/autorun"

class Something
  def dont_do_it
    :oops
  end
end

class RetryTest < Minitest::Test
  def test_different_return_values

JEG2

class HashLike
  def to_hash
    {a: 1, b: 2}
  end
end

def surprise(*args, keyword: nil)
  p args
end

JEG2

use std::collections::HashMap;

fn main() {
    let mut services = HashMap::new();
    services.insert("S1", vec!["A", "C"]);

    for (name, stops) in services.iter() {
        spawn( proc() {
            println!("{}", name);
        } );

JEG2

// The uncommented version of increment_all() works.  What I'm trying to
// understand is why I can't handle the return type as shown in the commented
// out version, which does not compile.

// fn increment_all<I: Iterator<int>>(numbers: I) -> I /* or Iterator<int> */ {
fn increment_all<'r, I: Iterator<int>>(numbers: I) -> std::iter::Map<'r, int, int, I> {
    numbers.map(|n| n + 1)
}

fn main() {