baweaver

class ShorthandProcCallMacro < Refactor::Rule
  matches do |node|
    node in [:block, receiver,
      [[:arg, arg_name]], [:send, [:lvar, ^arg_name], method_name]
    ]
  end

  replace do |_node, match_data|
    "#{match_data[:receiver].source}(&:#{match_data[:method_name]})"
  end

baweaver

require 'rubocop'

# Target - What I want to get to
# class ShorthandProcCallMacro2 < Rule
#   matches "$receiver.$method_call { |$arg| $arg.$arg_name }"
#   replaces "$receiver.$method_call(&:$arg_name)"
# end

class Literal
  def initialize(s)

baweaver

Refactoring with ASTs and Pattern Matching

Pattern matching in Ruby is not a well understood or frequently used feature, but when paired with ASTs it becomes an incredibly powerful tool for refactoring and code transformations.

Details

This talk is a deep dive into ASTs and RuboCop as refactoring and upgrade tools. With the advent of language servers this will become a very critical topic to have knowledge in to effectively work with manipulating Ruby code programatically.

Intended Audience

baweaver

Based on: https://www.youtube.com/watch?v=wf-4vexIOqc

I'll code you some Ruby, it's Ruby with C
Code me Lemur friends code
Oh I'll FFIddle some C if you'll debug it with me
And it's code me Lemur friends code

And it's code me Lemur friends
We're in a hurry then
We got a long sprint to go

baweaver

Agenda:

• Introductions - Coaches (5m)
  • Share names and pronouns
  • Brief history on what they do and how they work with Ruby
  • A tip or two on writing an awesome CFP
• Introductions - Prospective Speakers (15m)
  • Share names and pronouns
  • Brief history on what they do and how they work with Ruby

• Where are they in the process of writing their CFP (ideation, first draft, proofreading)

baweaver

class Cond
  IDENTITY = -> v { v }

  def initialize(if_cond: IDENTITY, then_branch: IDENTITY, else_branch: IDENTITY)
    @if_cond = if_cond
    @then_branch = then_branch
    @else_branch = else_branch
  end

  def call(v)

baweaver

KEYBOARD = [
  '1234567890-='.chars,
  'qwertyuiop[]'.chars,
  'asdfghjkl;\''.chars,
  'zxcvbnm,./'.chars,
]

def reasonable_typos(distance: 3)
  typo_map = Hash.new do |h, initial_key|
    h[initial_key] = {}

baweaver

module AccessedAttributes
  def self.included(klass)
    association_proxy = Module.new do
      def accessed_associations
        @_accessed_associations ||= []
      end
    end

    klass.reflect_on_all_associations.each do |association|
      name = association.name

baweaver

range = '0'..'255'

('1'..'5').map do |v|
  {
    v: v,
    teq: range === v,
    include?: range.include?(v)
  }
end
#  => [

baweaver

IDENTITY = -> v { v }

def proc_line(**fns)
  fns.reduce(IDENTITY) { |fn, (m, args)|
    fn >> m.to_proc.then { |m_proc| -> v { m_proc.call(v, *args) } }
  }
end

[50, 100, 300, 5000].map(&proc_line(
  to_s: 2, chars: nil, reverse: nil, join: nil, to_i: 2