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Big-O Time Complexities for Elixir data structures

Map [1]

Operation	Time Complexity
Access	O(log n)
Search	O(log n)
Insertion	O(n) for < 32 elements, O(log n) for >= 32 elements [2]
Deletion	O(n) for < 32 elements, O(log n) for >= 32 elements

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# TODO: Extract into it's own library
defmodule AbsintheSocket do
  require Logger
  alias Phoenix.Channels.GenSocketClient
  @behaviour GenSocketClient

  @control_topic "__absinthe__:control"

  defdelegate fetch(term, key), to: Map
  defdelegate get(term, key, default), to: Map

collegeimprovements

How to get an awesome neovim setup that runs tests asynchronously in a neoterm split

Example

Installing neovim

brew install neovim/neovim/neovim

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import "../css/app.scss"
import "phoenix_html"
import {Socket} from "phoenix"
import topbar from "topbar"
import {LiveSocket} from "phoenix_live_view"
import Alpine from 'alpinejs'
window.Alpine = Alpine
Alpine.start()

let csrfToken = document.querySelector("meta[name='csrf-token']").getAttribute("content")

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defmodule MyApp.Foo do
  @on_definition MyApp.SpecToCallback
  
  @spec bar(String.t()) :: String.t()
  def bar(foobar) do
    impl().bar(foobar)
  end
  
  defp impl, do: Application.get_env(:my_app, :my_app_foo_impl, __MODULE__.DefaultImpl)
end

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# Step 1

def create_subscription(email, plan_id, payment_method_id) do
  with %User{customer_id: nil, name: name} = user <-
         Repo.get_by(User, email: email),
       {:ok, %Stripe.Customer{id: customer_id}} <-
         Stripe.Customer.create(%{
           name: name,
           email: email,
           payment_method: payment_method_id,

collegeimprovements

How to create an HTTPS certificate for localhost domains

This focuses on generating the certificates for loading local virtual hosts hosted on your computer, for development only.

Do not use self-signed certificates in production ! For online certificates, use Let's Encrypt instead (tutorial).

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Generate ssl certificates with Subject Alt Names on OSX

Open ssl.conf in a text editor.

Edit the domain(s) listed under the [alt_names] section so that they match the local domain name you want to use for your project, e.g.

DNS.1   = my-project.dev

Additional FQDNs can be added if required:

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# This is just a cheat sheet:

# On production
sudo -u postgres pg_dump database | gzip -9 > database.sql.gz

# On local
scp -C production:~/database.sql.gz
dropdb database && createdb database
gunzip < database.sql.gz | psql database

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Pushing to Multiple Git Repos

If a project has to have multiple git repos (e.g. Bitbucket and Github) then it's better that they remain in sync.

Usually this would involve pushing each branch to each repo in turn, but actually Git allows pushing to multiple repos in one go.

If in doubt about what git is doing when you run these commands, just