havenwood

module ShareableLambda
  UNSET = Object.new.freeze
  private_constant :UNSET

  refine Kernel do
    private

    def lambda(shareable: false, self: UNSET, &block)
      receiver = {self:}[:self]

havenwood

require_relative "enumerable-parallel"

using Enumerable::Parallel.new(pool_size: 2)

(1..4).each do |number|
  sleep 1
  puts "#{number}\n"
end
##
# One second later...

havenwood

require_relative "pattern_matchable"

class Color
  extend PatternMatchable

  array_pattern :red, :green, :blue
  hash_pattern :red, :green, :blue,
    hex: -> { format "#%06x", packed },
    brightness: -> { (red * 299 + green * 587 + blue * 114).fdiv(1_000) }

havenwood

require "fiddle"

require_relative "settable_superclass"

class Klass
  using SettableSuperclass

  HEAP_TYPE = ->(obj) { Fiddle::Pointer.new(Fiddle.dlwrap(obj))[0, Fiddle::SIZEOF_VOIDP].unpack1("J") & 0x1f }
  private_constant :HEAP_TYPE

havenwood

[2, 3, 1].sort_by { Reverse[it] }
#=> 3, 2, 1

havenwood

require 'optparse'

module Kernel
  def OptionParser(&)
    fields = OptionParser.new(&).top.list.filter_map do |option|
      if option.is_a?(OptionParser::Switch)
        name = option.long&.first || option.short&.first
        name.delete_prefix('-').delete_prefix('-').to_sym
      end
    end

havenwood

class Alert < Module
  COLORS = {red: 31, yellow: 33, blue: 34, magenta: 35, cyan: 36}

  def initialize(message: nil, color: :red)
    super()
    @message = message
    @color = COLORS.fetch(color)
  end

  def included(base)

havenwood

rev

Single-file version control. Lighter than RCS.

Install

cp rev.rb /usr/local/bin/rev

Requires Ruby, diff and patch. Colored output when git is available.

havenwood

module Example
  ONCE = Once.new

  def self.once
    ONCE.call do
      # work
    end
  end
end

havenwood

defmodule FizzBuzz.Native do
  @moduledoc false

  use Rustler, otp_app: :fizz_buzz

  def classify(_nums), do: :erlang.nif_error(:nif_not_loaded)
end