Download as PDF, PPTX
![-module(my_module).
-export([hello/1]).
hello(Str) ->
my_helper(Str).
my_helper(Str) ->
string:reverse(string:uppercase(Str)).](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-18-2048.jpg)
![-module(my_module).
-export([hello/1]).
hello(Str) ->
my_helper(Str).
my_helper(Str) ->
string:reverse(string:uppercase(Str)).
defmodule MyModule do
def hello(str) do
my_helper(str)
end
defp my_helper(str) do
str
|> String.upcase()
|> String.reverse()
end
end](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-19-2048.jpg)
![# Install erlang
$ asdf plugin-add erlang
$ asdf list-all erlang # will list all the available versions
$ asdf install erlang 20.3.7
$ asdf global erlang 20.3.7
# Install Elixir
$ asdf plugin-add elixir
$ asdf list-all elixir
$ asdf install elixir 1.6.5
$ asdf global elixir 1.6.5
# [Optional] Install Node](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-24-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-32-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-33-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-34-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-35-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-36-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-37-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]
# Structs](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-38-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]
# Structs
defmodule User do
end](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-39-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]
# Structs
defmodule User do
defstruct [:first_name, :last_name, username: "Guest"]
end](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-40-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]
# Structs
defmodule User do
defstruct [:first_name, :last_name, username: "Guest"]
end
%User{first_name: "Pawel", last_name: "Dawczak"}](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-41-2048.jpg)
![# Lists
[1, 2, 3] # => [1, 2, 3]
# Tuples
{:ok, "Test"} # => {:ok, "Test"}
# Maps
map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"}
map[:first_name] # => "Pawel"
# Keyword Lists
opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
opts[:per_page] # => 3
Keyword.get_values(opts, :per_page) # => [3, 5]
# Structs
defmodule User do
defstruct [:first_name, :last_name, username: "Guest"]
end
%User{first_name: "Pawel", last_name: "Dawczak"}
# => User{first_name: "Pawel", last_name: "Dawczak", username: "Guest"}](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-42-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-49-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-50-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-51-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-52-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-53-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-54-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
Enum.reduce(1..3, 0, &(&1 + &2)) # => 6](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-55-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
Enum.reduce(1..3, 0, &(&1 + &2)) # => 6
Enum.reduce(1..3, 0, &+/2) # => 6](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-56-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
Enum.reduce(1..3, 0, &(&1 + &2)) # => 6
Enum.reduce(1..3, 0, &+/2) # => 6
pass = "MySecretPass123"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-57-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
Enum.reduce(1..3, 0, &(&1 + &2)) # => 6
Enum.reduce(1..3, 0, &+/2) # => 6
pass = "MySecretPass123"
Enum.map([3, 8, 14], fn x -> String.at(pass, x) end) # => ["e", "P", "3"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-58-2048.jpg)
![# Comprehensions
for x <- (1..5),
y <- [:blue, :red],
rem(x, 2) == 0,
do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
# Higher-order functions
Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
Enum.reduce(1..3, 0, &(&1 + &2)) # => 6
Enum.reduce(1..3, 0, &+/2) # => 6
pass = "MySecretPass123"
Enum.map([3, 8, 14], fn x -> String.at(pass, x) end) # => ["e", "P", "3"]
Enum.map([3, 8, 14], &String.at(pass, &1)) # => ["e", "P", "3"]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-59-2048.jpg)
![x = 1
1 = x
2 = x
** (MatchError) no match of right hand side value: 1
^x = 1 # ^ - pin operator
^x = 2
list = [20, 21, 22]
[a, b, c] = list
a # => 20
b # => 21
[a, ^x, c] = list
** (MatchError) no match of right hand side value: [20, 21, 22]
hd(list) # => 20
tl(list) # => [21, 22]
[head | tail] = list
head # => 20
tail # => [21, 22]
[a2, 21 | tail] = list
a2 # => 20
tail # => [22]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-61-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-67-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end
p = %Employee{name: "Pawel", lang: "Elixir"}](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-68-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end
p = %Employee{name: "Pawel", lang: "Elixir"}
%{name: name} = p
name # => "Pawel"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-69-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end
p = %Employee{name: "Pawel", lang: "Elixir"}
%{name: name} = p
name # => "Pawel"
%Employee{name: name} = p
name # => "Pawel"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-70-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end
p = %Employee{name: "Pawel", lang: "Elixir"}
%{name: name} = p
name # => "Pawel"
%Employee{name: name} = p
name # => "Pawel"
lang = "Elixir"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-71-2048.jpg)
![map = %{a: "Foo", b: "Bar"}
%{a: a} = map
a # => "Foo"
%{a: "Baz", b: b} = map
** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
defmodule Employee do
defstruct [:name, :lang]
end
p = %Employee{name: "Pawel", lang: "Elixir"}
%{name: name} = p
name # => "Pawel"
%Employee{name: name} = p
name # => "Pawel"
lang = "Elixir"
%Employee{name: name, lang: ^lang} = p
name # => "Pawel"](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-72-2048.jpg)
![File.read("./nice_file") # => {:ok, "Hello World! Nice to see you all!n"}
File.read("./non_existing_one") # => {:error, :enoent}
File.read!("./non_existing_one")
** (File.Error) could not read file "./non_existing_one": no such file or directory
HTTPoison.get("https://google.com")
{:ok,
%HTTPoison.Response{
body: "...",
headers: [
{"Location", "https://www.google.com/"},
{"Content-Type", "text/html; charset=UTF-8"},
{"Cache-Control", "public, max-age=2592000"},
{"Server", "gws"},
{"Content-Length", "220"},
{"X-Frame-Options", "SAMEORIGIN"},
],
request_url: "https://google.com",
status_code: 301
}}](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-78-2048.jpg)
![# 2. map
M.map([], fn x -> x * x end) # => []
M.map([1, 2, 3], fn x -> x * x end) # => [1, 4, 9]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-91-2048.jpg)
![# 2. map
defmodule M do
def map(list, fun), do: do_map(list, fun, [])
defp do_map([], _fun, acc), do: Enum.reverse(acc)
defp do_map([head | tail], fun, acc) do
result = fun.(head)
do_map(tail, fun, [result | acc])
end
end
M.map([], fn x -> x * x end) # => []
M.map([1, 2, 3], fn x -> x * x end) # => [1, 4, 9]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-92-2048.jpg)
![# 3. dedup
[1, 1, 1, 2, 3, 3]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-95-2048.jpg)
![# 3. dedup
[1, 1, 1, 2, 3, 3] => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-96-2048.jpg)
![# 3. dedup
defmodule D do
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-102-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-103-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
defp do_dedup([], acc), do: Enum.reverse(acc)
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-104-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
defp do_dedup([], acc), do: Enum.reverse(acc)
defp do_dedup([num, num | tail], acc) do
do_dedup(tail, [{2, num} | acc])
end
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-105-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
defp do_dedup([], acc), do: Enum.reverse(acc)
defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do
do_dedup(tail, [{cnt + 1, num} | acc_tail])
end
defp do_dedup([num, num | tail], acc) do
do_dedup(tail, [{2, num} | acc])
end
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-106-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
defp do_dedup([], acc), do: Enum.reverse(acc)
defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do
do_dedup(tail, [{cnt + 1, num} | acc_tail])
end
defp do_dedup([num, num | tail], acc) do
do_dedup(tail, [{2, num} | acc])
end
defp do_dedup([head | tail], acc), do: do_dedup(tail, [head | acc])
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-107-2048.jpg)
![# 3. dedup
defmodule D do
def dedup(list), do: do_dedup(list, [])
defp do_dedup([], acc), do: Enum.reverse(acc)
defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do
do_dedup(tail, [{cnt + 1, num} | acc_tail])
end
defp do_dedup([num, num | tail], acc) do
do_dedup(tail, [{2, num} | acc])
end
defp do_dedup([head | tail], acc), do: do_dedup(tail, [head | acc])
end
D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4]
D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-108-2048.jpg)
![# 4. 5 most common words - eager approach
defmodule Eager do
def answer do
File.read!("moby.txt")
|> String.split("n")
|> Enum.map(%String.trim/1)
|> Enum.filter(&(&1 != ""))
|> Enum.flat_map(&String.split/1)
|> Enum.filter(&(String.length(&1) > 3))
|> Enum.reduce(%{}, fn word, words ->
Map.update(words, word, 1, fn curr -> curr + 1 end)
end)
|> Enum.sort_by(fn {_word, count} -> count end, &>=/2)
|> Enum.take(5)
end
end
Eager.answer()
# => [{"that", 2692}, {"with", 1695}, {"this", 1169}, {"from", 1072}, {"have", 752}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-111-2048.jpg)
![# 5. 5 most common words - lazy approach
defmodule Lazy do
def answer do
File.stream!("moby.txt")
|> Stream.map(&String.trim/1)
|> Stream.filter(&(&1 != ""))
|> Stream.flat_map(&String.split/1)
|> Stream.filter(&(String.length(&1) > 3))
|> Enum.reduce(%{}, fn word, words ->
Map.update(words, word, 1, fn curr -> curr + 1 end)
end)
|> Enum.sort_by(fn {_word, count} -> count end, &>=/2)
|> Enum.take(5)
end
end
Lazy.answer()
# => [{"that", 2692}, {"with", 1695}, {"this", 1169}, {"from", 1072}, {"have", 752}]](https://image.slidesharecdn.com/pre-bootcampintroductiontoelixir-180615102119/75/Pre-Bootcamp-introduction-to-Elixir-112-2048.jpg)
Uploaded byPaweł Dawczak
Pre-Bootcamp introduction to Elixir
This document provides an introduction to the Elixir programming language. It discusses what Elixir is, how to get started with installation and configuration of Elixir and Erlang, basic and compound data types in Elixir, functions and modules, and higher-order functions and comprehensions. Key topics covered include installing Elixir using ASDF, basic data types like integers, floats, atoms, and more, functions and anonymous functions, modules, and Enum functions like map, reduce, and comprehensions.
Pre-Bootcamp introduction to Elixir
- 1.
- 2. # 1. Introduction- what is Elixir, how to start? # 2. Basic and compound data types # 3. Functions and modules # 4. Let’s talk about `=` # 5. Let’s have some fun! # 6. Let’s talk about `mix` # 7. Let’s talk about dependencies # 8. Suggestions where to find more information # 9. QA
- 3. # What isElixir?
- 8.
- 11.
- 12.
- 13.
- 14. Erlang/OTP O - Open T- Telecom P - Platform
- 16.
- 18.
- 19. -module(my_module). -export([hello/1]). hello(Str) -> my_helper(Str). my_helper(Str) -> string:reverse(string:uppercase(Str)). defmoduleMyModule do def hello(str) do my_helper(str) end defp my_helper(str) do str |> String.upcase() |> String.reverse() end end
- 20. # Where doI start?
- 22. # Install erlang $asdf plugin-add erlang $ asdf list-all erlang # will list all the available versions $ asdf install erlang 20.3.7 $ asdf global erlang 20.3.7
- 23. # Install erlang $asdf plugin-add erlang $ asdf list-all erlang # will list all the available versions $ asdf install erlang 20.3.7 $ asdf global erlang 20.3.7 # Install Elixir $ asdf plugin-add elixir $ asdf list-all elixir $ asdf install elixir 1.6.5 $ asdf global elixir 1.6.5
- 24. # Install erlang $asdf plugin-add erlang $ asdf list-all erlang # will list all the available versions $ asdf install erlang 20.3.7 $ asdf global erlang 20.3.7 # Install Elixir $ asdf plugin-add elixir $ asdf list-all elixir $ asdf install elixir 1.6.5 $ asdf global elixir 1.6.5 # [Optional] Install Node
- 25. # Basic datatypes
- 26. nil # =>nil true # => true :test # => :test
- 27. nil # =>nil true # => true :test # => :test 1 # => 1 1.2 # => 1.2 "Testing" # => "Testing" 'Testing' # => 'Testing'
- 28. nil # =>nil true # => true :test # => :test 1 # => 1 1.2 # => 1.2 "Testing" # => "Testing" 'Testing' # => 'Testing' is_binary("Testing") # => true is_binary('Testing') # => false is_list("Testing") # => false is_list('Testing') # => true
- 29. nil # =>nil true # => true :test # => :test 1 # => 1 1.2 # => 1.2 "Testing" # => "Testing" 'Testing' # => 'Testing' is_binary("Testing") # => true is_binary('Testing') # => false is_list("Testing") # => false is_list('Testing') # => true pid(0, 13, 0) # => #PID<0.13.0>
- 30. nil # =>nil true # => true :test # => :test 1 # => 1 1.2 # => 1.2 "Testing" # => "Testing" 'Testing' # => 'Testing' is_binary("Testing") # => true is_binary('Testing') # => false is_list("Testing") # => false is_list('Testing') # => true pid(0, 13, 0) # => #PID<0.13.0> make_ref() # => #Reference<0.1816712181.2865233921.217076> # The reference is unique among connected nodes.
- 31. # Compound datatypes
- 32. # Lists [1, 2,3] # => [1, 2, 3]
- 33. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"}
- 34. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel"
- 35. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5]
- 36. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3
- 37. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5]
- 38. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5] # Structs
- 39. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5] # Structs defmodule User do end
- 40. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5] # Structs defmodule User do defstruct [:first_name, :last_name, username: "Guest"] end
- 41. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5] # Structs defmodule User do defstruct [:first_name, :last_name, username: "Guest"] end %User{first_name: "Pawel", last_name: "Dawczak"}
- 42. # Lists [1, 2,3] # => [1, 2, 3] # Tuples {:ok, "Test"} # => {:ok, "Test"} # Maps map = %{first_name: "Pawel", last_name: "Dawczak"} # => %{first_name: "Pawel", last_name: "Dawczak"} map[:first_name] # => "Pawel" # Keyword Lists opts = [per_page: 3, current_page: 1, per_page: 5] # => [per_page: 3, current_page: 1, per_page: 5] opts[:per_page] # => 3 Keyword.get_values(opts, :per_page) # => [3, 5] # Structs defmodule User do defstruct [:first_name, :last_name, username: "Guest"] end %User{first_name: "Pawel", last_name: "Dawczak"} # => User{first_name: "Pawel", last_name: "Dawczak", username: "Guest"}
- 43. # Functions andmodules
- 44. # Functions inc =fn x -> x + 1 end inc.(3) # => 4
- 45. # Functions inc =fn x -> x + 1 end inc.(3) # => 4 # Capture operator dec = &(&1 - 1) dec.(3) # => 2
- 46. # Functions inc =fn x -> x + 1 end inc.(3) # => 4 # Capture operator dec = &(&1 - 1) dec.(3) # => 2 # Modules defmodule MyModule do end
- 47. # Functions inc =fn x -> x + 1 end inc.(3) # => 4 # Capture operator dec = &(&1 - 1) dec.(3) # => 2 # Modules defmodule MyModule do def square(x) do x * 2 end end MyModule.square(4) # => 8
- 48. # Functions inc =fn x -> x + 1 end inc.(3) # => 4 # Capture operator dec = &(&1 - 1) dec.(3) # => 2 # Modules defmodule MyModule do def square(x) do x * 2 end def multi(x, y), do: x * y end MyModule.square(4) # => 8 MyModule.multi(3, 4) # => 12
- 49. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"]
- 50. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions
- 51. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"]
- 52. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"]
- 53. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"]
- 54. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6
- 55. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6 Enum.reduce(1..3, 0, &(&1 + &2)) # => 6
- 56. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6 Enum.reduce(1..3, 0, &(&1 + &2)) # => 6 Enum.reduce(1..3, 0, &+/2) # => 6
- 57. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6 Enum.reduce(1..3, 0, &(&1 + &2)) # => 6 Enum.reduce(1..3, 0, &+/2) # => 6 pass = "MySecretPass123"
- 58. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6 Enum.reduce(1..3, 0, &(&1 + &2)) # => 6 Enum.reduce(1..3, 0, &+/2) # => 6 pass = "MySecretPass123" Enum.map([3, 8, 14], fn x -> String.at(pass, x) end) # => ["e", "P", "3"]
- 59. # Comprehensions for x<- (1..5), y <- [:blue, :red], rem(x, 2) == 0, do: "#{x * x}-#{y}" # => ["4-blue", "4-red", "16-blue", "16-red"] # Higher-order functions Enum.map([1, 2, 3], fn num -> to_string(num) end) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string(&1)) # => ["1", "2", "3"] Enum.map([1, 2, 3], &to_string/1) # => ["1", "2", "3"] Enum.reduce(1..3, 0, fn num, acc -> num + acc end) # => 6 Enum.reduce(1..3, 0, &(&1 + &2)) # => 6 Enum.reduce(1..3, 0, &+/2) # => 6 pass = "MySecretPass123" Enum.map([3, 8, 14], fn x -> String.at(pass, x) end) # => ["e", "P", "3"] Enum.map([3, 8, 14], &String.at(pass, &1)) # => ["e", "P", "3"]
- 60. # Let’s talkabout `=`
- 61. x = 1 1= x 2 = x ** (MatchError) no match of right hand side value: 1 ^x = 1 # ^ - pin operator ^x = 2 list = [20, 21, 22] [a, b, c] = list a # => 20 b # => 21 [a, ^x, c] = list ** (MatchError) no match of right hand side value: [20, 21, 22] hd(list) # => 20 tl(list) # => [21, 22] [head | tail] = list head # => 20 tail # => [21, 22] [a2, 21 | tail] = list a2 # => 20 tail # => [22]
- 62. map = %{a:"Foo", b: "Bar"}
- 63. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo"
- 64. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map
- 65. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"}
- 66. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do end
- 67. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end
- 68. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end p = %Employee{name: "Pawel", lang: "Elixir"}
- 69. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end p = %Employee{name: "Pawel", lang: "Elixir"} %{name: name} = p name # => "Pawel"
- 70. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end p = %Employee{name: "Pawel", lang: "Elixir"} %{name: name} = p name # => "Pawel" %Employee{name: name} = p name # => "Pawel"
- 71. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end p = %Employee{name: "Pawel", lang: "Elixir"} %{name: name} = p name # => "Pawel" %Employee{name: name} = p name # => "Pawel" lang = "Elixir"
- 72. map = %{a:"Foo", b: "Bar"} %{a: a} = map a # => "Foo" %{a: "Baz", b: b} = map ** (MatchError) no match of right hand side value: %{a: "Foo", b: "Bar"} defmodule Employee do defstruct [:name, :lang] end p = %Employee{name: "Pawel", lang: "Elixir"} %{name: name} = p name # => "Pawel" %Employee{name: name} = p name # => "Pawel" lang = "Elixir" %Employee{name: name, lang: ^lang} = p name # => "Pawel"
- 73.
- 74. File.read("./nice_file") # =>{:ok, "Hello World! Nice to see you all!n"}
- 75. File.read("./nice_file") # =>{:ok, "Hello World! Nice to see you all!n"} File.read("./non_existing_one") # => {:error, :enoent}
- 76. File.read("./nice_file") # =>{:ok, "Hello World! Nice to see you all!n"} File.read("./non_existing_one") # => {:error, :enoent} File.read!("./non_existing_one") ** (File.Error) could not read file "./non_existing_one": no such file or directory
- 77. File.read("./nice_file") # =>{:ok, "Hello World! Nice to see you all!n"} File.read("./non_existing_one") # => {:error, :enoent} File.read!("./non_existing_one") ** (File.Error) could not read file "./non_existing_one": no such file or directory HTTPoison.get("https://google.com")
- 78. File.read("./nice_file") # =>{:ok, "Hello World! Nice to see you all!n"} File.read("./non_existing_one") # => {:error, :enoent} File.read!("./non_existing_one") ** (File.Error) could not read file "./non_existing_one": no such file or directory HTTPoison.get("https://google.com") {:ok, %HTTPoison.Response{ body: "...", headers: [ {"Location", "https://www.google.com/"}, {"Content-Type", "text/html; charset=UTF-8"}, {"Cache-Control", "public, max-age=2592000"}, {"Server", "gws"}, {"Content-Length", "220"}, {"X-Frame-Options", "SAMEORIGIN"}, ], request_url: "https://google.com", status_code: 301 }}
- 79. String.reverse(String.upcase(format.(String.replace("My Content -1", ~r/W/, "_"))))
- 80. String.reverse(String.upcase(format.(String.replace("My Content -1", ~r/W/, "_")))) # Pipe operator String.replace("My Content - 1", ~r/W/, "_") |> format.() |> String.upcase() |> String.reverse()
- 81. String.reverse(String.upcase(format.(String.replace("My Content -1", ~r/W/, "_")))) # Pipe operator String.replace("My Content - 1", ~r/W/, "_") |> format.() |> String.upcase() |> String.reverse() # Pipe operator in action
- 82. String.reverse(String.upcase(format.(String.replace("My Content -1", ~r/W/, "_")))) # Pipe operator String.replace("My Content - 1", ~r/W/, "_") |> format.() |> String.upcase() |> String.reverse() # Pipe operator in action process = fn {:ok, %{body: body}} -> # parse the body, etc… {:error, error_message} -> Logger.error("Request failed due to: #{error_message}") end
- 83. String.reverse(String.upcase(format.(String.replace("My Content -1", ~r/W/, "_")))) # Pipe operator String.replace("My Content - 1", ~r/W/, "_") |> format.() |> String.upcase() |> String.reverse() # Pipe operator in action process = fn {:ok, %{body: body}} -> # parse the body, etc… {:error, error_message} -> Logger.error("Request failed due to: #{error_message}") end "https://google.com" |> HTTPoison.get() |> process.()
- 85. # Let thefun begin!
- 86.
- 88. # 1. Fibonacci! defmoduleFib do def of(0), do: 1 def of(1), do: 1 def of(n) when n > 1, do: of(n-1) + of(n-2) end Fib.of(5) Fib.of(-6)
- 90.
- 91. # 2. map M.map([],fn x -> x * x end) # => [] M.map([1, 2, 3], fn x -> x * x end) # => [1, 4, 9]
- 92. # 2. map defmoduleM do def map(list, fun), do: do_map(list, fun, []) defp do_map([], _fun, acc), do: Enum.reverse(acc) defp do_map([head | tail], fun, acc) do result = fun.(head) do_map(tail, fun, [result | acc]) end end M.map([], fn x -> x * x end) # => [] M.map([1, 2, 3], fn x -> x * x end) # => [1, 4, 9]
- 94.
- 95. # 3. dedup [1,1, 1, 2, 3, 3]
- 96. # 3. dedup [1,1, 1, 2, 3, 3] => [{3, 1}, 2, {2, 3}]
- 97.
- 98. # 3. dedup 1 1 13 list acc
- 99. # 3. dedup 1 {2,1} 3 list acc
- 100. # 3. dedup {3,1} 3 list acc
- 101. # 3. dedup listacc 3 {3, 1} reversed
- 102. # 3. dedup defmoduleD do end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 103. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 104. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) defp do_dedup([], acc), do: Enum.reverse(acc) end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 105. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) defp do_dedup([], acc), do: Enum.reverse(acc) defp do_dedup([num, num | tail], acc) do do_dedup(tail, [{2, num} | acc]) end end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 106. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) defp do_dedup([], acc), do: Enum.reverse(acc) defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do do_dedup(tail, [{cnt + 1, num} | acc_tail]) end defp do_dedup([num, num | tail], acc) do do_dedup(tail, [{2, num} | acc]) end end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 107. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) defp do_dedup([], acc), do: Enum.reverse(acc) defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do do_dedup(tail, [{cnt + 1, num} | acc_tail]) end defp do_dedup([num, num | tail], acc) do do_dedup(tail, [{2, num} | acc]) end defp do_dedup([head | tail], acc), do: do_dedup(tail, [head | acc]) end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 108. # 3. dedup defmoduleD do def dedup(list), do: do_dedup(list, []) defp do_dedup([], acc), do: Enum.reverse(acc) defp do_dedup([num | tail], [{cnt, num} | acc_tail]) do do_dedup(tail, [{cnt + 1, num} | acc_tail]) end defp do_dedup([num, num | tail], acc) do do_dedup(tail, [{2, num} | acc]) end defp do_dedup([head | tail], acc), do: do_dedup(tail, [head | acc]) end D.dedup([1, 2, 3, 4]) # => [1, 2, 3, 4] D.dedup([1, 1, 1, 2, 3, 3]) # => [{3, 1}, 2, {2, 3}]
- 110. # 4. 5most common words - eager approach
- 111. # 4. 5most common words - eager approach defmodule Eager do def answer do File.read!("moby.txt") |> String.split("n") |> Enum.map(%String.trim/1) |> Enum.filter(&(&1 != "")) |> Enum.flat_map(&String.split/1) |> Enum.filter(&(String.length(&1) > 3)) |> Enum.reduce(%{}, fn word, words -> Map.update(words, word, 1, fn curr -> curr + 1 end) end) |> Enum.sort_by(fn {_word, count} -> count end, &>=/2) |> Enum.take(5) end end Eager.answer() # => [{"that", 2692}, {"with", 1695}, {"this", 1169}, {"from", 1072}, {"have", 752}]
- 112. # 5. 5most common words - lazy approach defmodule Lazy do def answer do File.stream!("moby.txt") |> Stream.map(&String.trim/1) |> Stream.filter(&(&1 != "")) |> Stream.flat_map(&String.split/1) |> Stream.filter(&(String.length(&1) > 3)) |> Enum.reduce(%{}, fn word, words -> Map.update(words, word, 1, fn curr -> curr + 1 end) end) |> Enum.sort_by(fn {_word, count} -> count end, &>=/2) |> Enum.take(5) end end Lazy.answer() # => [{"that", 2692}, {"with", 1695}, {"this", 1169}, {"from", 1072}, {"have", 752}]
- 113. # Let’s talkabout `mix`
- 150. # Let’s talkabout dependencies
- 167. # Where togo next?
- 168.
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- 170.
- 171.
- 172.
- 173.
- 174.
- 175. Thank You! Pre-bootcamp introduction toElixir Paweł Dawczak