JoshCheek

import functools

class LList:
    @classmethod
    def fromArray(cls, array):
        return functools.reduce(lambda ll, val: ll.append(val), array, cls())

    def __init__(self):                   self.isEmpty = True
    def append(self, val):                return LNode(val, self)
    def __iter__(self):                   return self

JoshCheek

# Note1: all `...` below mean "etcetera", like psuedocode, not implying the new Ruby 3 syntax
# Note2: `obj.()` is syntactic sugar for `obj.call()`

# Given an invocation like this:
OnboardOrganization.(arg1, arg2, ...)

# Here are some possible ways you could implement it:

# 1. If the definition fits in a s single method, you can toss it on a module
# You'd choose a module b/c you don't want a class here since you don't want to

JoshCheek

# This fixes a bug that the code below triggered. SiB uses String#<< on this line:
# https://github.com/JoshCheek/seeing_is_believing/blob/46d49a53a68ec22edd52322ad0f1192ef2d77f51/lib/seeing_is_believing/event_stream/producer.rb#L155
# So it should include this alias in the Safe refinements here:
# https://github.com/JoshCheek/seeing_is_believing/blob/46d49a53a68ec22edd52322ad0f1192ef2d77f51/lib/seeing_is_believing/safe.rb#L47-L51
module SeeingIsBelieving::Safe
  refine String do
    alias << <<
  end
end

JoshCheek

# Example works if done in args instead of local var assignment:
-> a, b=nil, c { {a: a, b: b, c: c} }[1, 2] # => {:a=>1, :b=>nil, :c=>2}

# Lib could, eg reflect on param types
def arg_parser(&block)
  lambda do |argv|
    argv, args = argv.dup, []
    keywords = block.parameters.filter_map { |t, n| [n, false] if t == :keyreq }.to_h
    while (arg = argv.shift)
      next args << arg unless /^--?(.*)/ =~ arg

JoshCheek

RUBY_VERSION # => "2.7.2"
require 'fiddle'

User = Struct.new :name

class NullUser < NilClass
  # We have no way to allocate a new NullUser... BUT! We can hack around this
  # by making a new object and setting its class pointer to point at NullUser
  def self.new(*)
    instance     = Object.new

JoshCheek

# Remove the `-tco` from the end to run it without tailcall optimization
env RUBY_THREAD_VM_STACK_SIZE=100 ruby -e '
RubyVM::InstructionSequence.new(<<~RUBY, tailcall_optimization: !!$tco).eval
def fibo(n, a=0, b=1)
  return a if n.zero?
  fibo n-1, a+b, a
end
RUBY

p fibo 500' -s -- -tco

JoshCheek

%ul
  - @omghis.each do |omghi|
    %li
      = omghi.wtf
      = image_tag omghi.media.variant(resize: "339x243") if omghi.media.present?

:css
  .omgsection { border: 1px solid black; }

= form_for @omghi, controller: :omghi, method: :create do |f|

JoshCheek

require 'pg'

PG.connect(dbname: 'postgres').tap do |db|
  db.exec "drop database if exists postgresql_experiments"
  db.exec "create database postgresql_experiments"
end

PG.connect(dbname: 'postgresql_experiments').exec(<<~SQL).to_a
create table tree (id int, parent_id int);

JoshCheek

Refactoring Suggestions

Hey, this morning I was thinking about the code we looked at yesterday, and how I'd refactor it. I came up with a few ideas, generally with overlapping reasons for the changes. I'm on a long train ride to St. Louis, and figured I'd write up what things I noticed and how I would make changes based on those things. It got a little long, b/c I had a few goals with it:

• I wanted to make sure I explained my reasoning so that it wasn't just a religious

JoshCheek

# Users can fork the process, SiB still works
if !fork
  Process.pid # => 6669
else
  Process.pid # => 6668

  # Users can exec, SiB still works
  exec "echo users can exec, SiB still works" # printing is displayed at eof
end