Elixir, Zero to Web

An introduction to the Elixir programming language that takes us from install to a functioning web application built with the Phoenix framework.

Transcript

1. DevMynd Elixir, Zero to Web JC Grubbs @thegrubbsian devmynd.com
2. DevMynd 1 Introduction 2 Ecosystem 3 Web dev 4 Deployment
3. DevMynd What is Elixir?
4. DevMynd Erlang
5. DevMynd BEAM Virtual Machine
6. DevMynd Pattern matching Immutability Actor model
7. DevMynd Metaprogramming Polymorphism Accessible syntax Tooling
8. DevMynd Homoiconic
9. DevMynd Erlang…Lisp
10. DevMynd brew install elixir cinst elixir
11. DevMynd IO.puts "Hello World!"
12. DevMynd 1 # integer 1.0 # float :atom # atom {1,2,"r"} # tuple ["a",2,3] # list %{foo: "bar"} # map
13. DevMynd "foo" <> "bar" #=> foobar true and true #=> true false or is_atom(:a) #=> true 1 || true #=> true nil && 13 #=> nil [1,2] ++ [3,4] #=> [1,2,3,4] [1,2,3] -- [2] #=> [1,3]
14. DevMynd defmodule Stringer do def down(str) do String.downcase(str) end def split(str) do String.split(str, " ") end end ! "The Quick Fox" |> Stringer.down |> Stringer.split ! #=> ["the", "quick", "fox"]
15. DevMynd defmodule Calc do def add(a, b \\ 1) do "Answer: #{a + b}" end end ! Calc.add(1,2) #=> Answer: 3
16. DevMynd name = "JC" ! greet = fn(greeting) -> "#{greeting}, #{name}!" end ! greet.("Hello") #=> Hello, JC!
17. DevMynd x = 1 #=> 1 x #=> 1 1 = x #=> 1 2 = x #=> (MatchError) no match of #=> right hand side value: 1
18. DevMynd {a,b} = {:foo,"bar"} #=> {:foo, "bar"} a #=> :foo b #=> bar
19. DevMynd {:ok,b} = {:ok,"bar"} #=> {:ok, "bar"} {:err,b} = {:ok,"bar"} #=> (NoMatchError)...
20. DevMynd list = [1, 2, 3] case list do [a|b] -> IO.puts(a) IO.puts(b) [] -> IO.puts "empty" end #=> 1 #=> [2, 3]
21. DevMynd defmodule NumList do def sum(list) do sum(list, 0) end ! defp sum([head|rest], acc) do sum(rest, head + acc) end ! defp sum([], acc) do acc end end NumList.sum(1,2,3) #=> 6
22. DevMynd a = 1 #=> 1 a = 2 #=> 2 ^a = 1 #=> (NoMatchError)
23. DevMynd use Foo Execute the __USING__ function import Foo Import functions as local require Foo Bring in Foo’s macros alias Foo Call Foo’s functions on an alias
24. DevMynd defmodule Foo.Bar do def baz(arg) do IO.puts arg end end ! defmodule Foo do import Foo.Bar def boo do baz(42) end end
25. DevMynd defmodule Foo.Bar do def baz(arg) do end def quux(arg) do end end ! defmodule Foo do import Foo.Bar, only: [:baz] def boo do quux(42) #=> undefined function end end
26. DevMynd defmodule Foo.Bar do def quux(arg) do end end ! defmodule Foo do alias Foo.Bar, as: Baz def boo do Baz.quux(42) end end
27. DevMynd defmodule Foo.Bar do def __USING__ do IO.puts "Using Foo.Bar" end end ! defmodule Foo do use Foo.Bar end #=> Using Foo.Bar
28. DevMynd defmodule Person do defstruct name: "", age: 0 end ! john = %Person{name: "John", age: 42} john.name #=> John john.age #=> 42 ! %{john | age: 43}
29. DevMynd foo.ex Files will be compiled foo.exs Scripting files, not pre-compiled
30. DevMynd IEx
31. DevMynd Mix
32. DevMynd Hex
33. DevMynd ExUnit
34. DevMynd defmodule CalcTest do use ExUnit.Case ! test "it sums" do assert Calc.sum([1,2,3]) == 6 end end
35. DevMynd Plug
36. DevMynd defmodule MyPlug do import Plug.Conn def init(options) do # initialize options ! options end def call(conn, _opts) do conn |> put_resp_content_type("text/plain") |> send_resp(200, "Hello world") end end ! Plug.Adapters.Cowboy.http MyPlug, []
37. DevMynd Phoenix
38. DevMynd Templates Views Controllers Router Plugs Webserver Channels Topics
39. DevMynd Phoenix Todo Sample App https://github.com/thegrubbsian/todo