bmitch

Books

• http://greenteapress.com/thinkpython/thinkpython.pdf
• https://automatetheboringstuff.com/
• http://www.obeythetestinggoat.com/pages/book.html

Video Courses

• https://www.udemy.com/automate/learn/v4/overview

Tutorials

• https://medium.com/crypto-currently/lets-build-the-tiniest-blockchain-e70965a248b

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defmodule Ticker do
    
    @interval 2000
    @name     :ticket

    def start do
        pid = spawn(__MODULE__, :generator, [[]])
        :global.register_name(@name, pid)
    end

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defmodule Parallel do
    def pmap(collection, fun) do
        me = self
        collection
        |> Enum.map(fn (elem) ->
            spawn_link fn -> (send me, { self, fun.(elem) }) end
        end)
        |> Enum.map(fn (pid) ->
            receive do { ^pid, result } -> result end
            end)

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defmodule Spawn1 do
    def greet do
        receive do
            {sender, msg} ->
                send sender, { :ok, "Hello, #{msg}" }
                greet
        end
    end
end

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defmodule Chain do
    def counter(next_pid) do
        receive do
            n ->
                send next_pid, n + 1
        end
    end

    def create_processes(n) do
        last = Enum.reduce 1..n, self,

bmitch

Creating a project tree:

mix new <project name>

Running tests:

mix test

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Back

Basics

Value Types

Represent numbers, names, ranges and regular expressions.

Integers

Can be written as:

• decimal (1234).

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Back

Immutability

• Once a variable a list such as [1, 2 ,3] you know it will always reference those same variables (until you rebind the variable).
• What if you need to add 100 to each element in [1, 2, 3]? Elixir produces a copy of the original, containing the new values.

This uses the [ head | tail ] operator to build a new list with head as the first element and tail as the rest:

list1 = [3, 2, 1]

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Elixir Notes

• Pattern Matching
• Immutability
• Basics
• Organizing a project

Misc notes

• String concatenation:

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Back

Pattern Matching

• = is not assignment in Elixir. More like an assertion.
• Succeeds if it can find a way of making left side equal to right side.

a = 1 #1
a + 3 #1

In thise cases the lef side is a variable and right side is an integer literal. So to make the match it binds the variable to the integer.