BrooklinJazz

defmodule Greeting do
  def say_hello(name) do
    "Hello #{name}"
  end  
  def say_hello(name) when name === "Brooklin" do
    "Oh it's just you again"
  end
end

Greeting.say_hello("Brooklin") # Hello Brooklin

BrooklinJazz

defmodule Greeting do
  def say_hello(name) when name === "Brooklin" do
    "Oh it's just you again"
  end
  def say_hello(name) do
    "Hello #{name}"
  end
end

Greeting.say_hello("Brooklin") # Oh it's just you again

BrooklinJazz

defmodule Greeting do
  def say_hello(name \\ "Brooklin") do
    "Hello #{name}"
  end
end

Greeting.say_hello() # Hello Brooklin

BrooklinJazz

defmodule M do
  def above_20?(val) do
     val > 20
  end
end
M.above_20?(21) # true

BrooklinJazz

String.length "a string" # 8 
String.contains?("string", "str") # true
String.at("mystring", 2) # s
String.slice("mystring", 2, 3)
String.split("my string", " ") # ["my", "string"]
String.reverse("string") # gnirts
String.upcase("string") # STRING 
String.downcase("STRING") # string
String.capitalize("string") # "String"

BrooklinJazz

# with string syntax
map = %{"key" => "value"}
Map.get(map, "key") # value

# with atom syntax
map = %{key: "value"}
Map.get(map, :key) # value

BrooklinJazz

Tuple.append({1}, 2) # {1, 2}
Tuple.duplicate(0, 5) # {0, 0, 0, 0, 0}
Tuple.insert_at({1, 3}, 1, 2) # {1, 2, 3}

BrooklinJazz

map = %{"key" => "value"}
%{map | "key" => "value2"} # %{"key" => "value2"}
%{map | "key2" => "value2"}
# ** (KeyError) key "key2" not found
    main.exs:3: (file)

BrooklinJazz

[head | tail] = [1,2,3]
head # 1
tail # [2, 3]

BrooklinJazz

List.last([1,2,3]) # 3
List.first([1, 2, 3]) # 1
List.delete([1,2,3], 1) # [2, 3]
List.delete_at([1,2,3], 0) # [2, 3]