Abusing pattern matching as a proc factory and subsequent invocation

worry.rb

# frozen_string_literal: true
require 'json'

module Proxy
  refine Object do
    def deconstruct_keys(methods)
      methods.to_h { |m| [m, ->(*a) { throw m, public_send(m, *a) }] }
    end
  end
end

class MyApp
  using Proxy
  attr_reader :parser

  def initialize
    JSON => {parse: parser}
    @parser = parser
  end
end

# Later that same program....
parser = MyApp.new.parser

# Obtain input
str = '{ "foo": [1,2,null] }'

# Parse
res = catch(:parse) { str => ^parser }

puts "result: #{res.inspect}"