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+# Elixir is a dynamic, functional language for building scalable
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+# and maintainable applications. Learn more: https://elixir-lang.org
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+
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+"Elixir" |> String.graphemes() |> Enum.frequencies()
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+#=> %{"E" => 1, "i" => 2, "l" => 1, "r" => 1, "x" => 1}
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+
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+
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+### Scalability ###
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+
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+# All Elixir code runs inside lightweight threads of execution (called processes)
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+# that are isolated and exchange information via messages:
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+
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+current_process = self()
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+
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+# Spawn an Elixir process (not an operating system one!)
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+spawn_link(fn ->
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+ send(current_process, {:msg, "hello world"})
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+end)
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+
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+# Block until the message is received
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+receive do
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+ {:msg, contents} -> IO.puts(contents)
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+end
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+
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+
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+### Fault-tolerance ###
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+
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+# To cope with failures, Elixir provides supervisors which describe
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+# how to restart parts of your system when things go awry, going back
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+# to a known initial state that is guaranteed to work:
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+
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+children = [
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+ TCP.Pool,
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+ {TCP.Acceptor, port: 4040}
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+]
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+
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+Supervisor.start_link(children, strategy: :one_for_one)
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+
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+
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+### Functional programming ###
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+
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+# Functional programming promotes a coding style that helps
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+# developers write code that is short, concise, and maintainable.
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+# One prominent example is pattern matching:
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+
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+%User{name: name, age: age} = User.get("John Doe")
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+name #=> "John Doe"
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+
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+# When mixed with guards, pattern matching allows us to elegantly
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+# match and assert specific conditions for some code to execute:
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+
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+def drive(%User{age: age}) when age >= 16 do
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+ # Code that drives a car
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+end
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+
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+drive(User.get("John Doe"))
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+#=> Fails if the user is under 16
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+
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+
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+### Extensibility and DSLs ###
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+
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+# Elixir has been designed to be extensible, letting developers
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+# naturally extend the language to particular domains,
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+# in order to increase their productivity.
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+
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+defmodule MathTest do
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+ use ExUnit.Case, async: true
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+
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+ test "can add two numbers" do
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+ assert 1 + 1 == 2
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+ end
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+end
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+
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+
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+### Erlang compatible ###
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+
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+# An Elixir programmer can invoke any Erlang function with no runtime cost:
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+
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+:crypto.hash(:md5, "Using crypto from Erlang OTP")
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+#=> <<192, 223, 75, 115, ...>>
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Henning Dieterichs