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Mix.install([:benchee])

defmodule LuhnChecksum do
  defguard is_even(x) when rem(x, 2) == 0

  def with_reverse(digits) do
    digits
    |> Enum.reverse()
    |> Enum.with_index(1)
    |> Enum.map(fn

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Mix.install([:benchee])

defmodule StringPerf do
  def concat([]), do: ""
  def concat([head | tail]), do: head <> concat(tail)

  def interpol([]), do: ""
  def interpol([head | tail]), do: "#{head}#{interpol(tail)}"

  def joiner(input), do: Enum.join(input, "")

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GenServer.reply/2

Check the other two files in this gist.

In the common.exs we show a standard approach (by the book) to handle incoming requests via handle_call/3 and {:reply, ...} return values. It blocks processing of all the coming requests until the one that is handled finished.

In contrast, in the reply.exs we leverage power of Task.async/1, GenServer.reply/2, and {:noreply, ...} return values. It allows our GenServer process incoming requests in parallel. Then the processing finished, we send results back to the original client (from pid).

Warning

Be careful, as this approach can lead to uncontrollable load to our GenServer.

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defmodule Clusty.Application do
  use Application

  @topologies local_epmd: [strategy: Cluster.Strategy.LocalEpmd]

  @impl true
  def start(_type, _args) do
    children = [
      {Cluster.Supervisor, [@topologies, [name: ClusterSupervisor]]},
      Pidgy

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Mix.install([:benchee])

defmodule Proteins do
  @stop "STOP"
  @err_msg "invalid codon"

  @codons %{
    "UGU" => "Cysteine",
    "UGG" => "Tryptophan",
    "UUU" => "Phenylalanine",

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name: Elixir CI

on:
  push:
    branches: ["master"]
  pull_request:
    branches: ["master"]

env:
  MIX_ENV: test

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Mix.install([
  {:benchee, "~> 1.0"}
])

defmodule Cruncher do
  def async(n) do
    1..n
    |> Task.async_stream(&(&1 ** 2))
    |> Enum.reduce(0, fn {:ok, s}, acc -> s + acc end)
  end

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Mix.install([
  {:benchee, "~> 1.0"}
])

defmodule BirdCond do
  def busy_days(list) do
    cond do
      list == [] -> 0
      hd(list) < 5 -> busy_days(tl(list))
      true -> 1 + busy_days(tl(list))

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# Origin: https://blog.sequin.io/how-we-used-elixirs-observer-to-hunt-down-bottlenecks/
defmodule Overload do
  # Define a CPU-intenstive work function, which can call itself
  # recursively (forever)
  def recursive do
    :public_key.generate_key({:rsa, 4096, 65537})
    recursive()
  end
end

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% Read more:
% - https://joearms.github.io/published/2013-11-21-My-favorite-erlang-program.html
% - https://ferd.ca/my-favorite-erlang-container.html
%
% How to run:
% $ erl
% > c(uni).
% {ok,uni}
% > uni:test().
% 30414093201713378043612608166064768844377641568960512000000000000