Scraps

bench_fib.rb

require 'benchmark/ips'

def simple_fib(n)
  return n if [0, 1].include?(n)
  simple_fib(n - 1) + simple_fib(n - 2)
end

def rec_fib(n)
  rec = -> (a, b, n) { n == 0 ? a : rec.call(b, a + b, n - 1) }
  rec.call(0, 1, n)
end

upto = 30

Benchmark.ips do |x|
  x.report("simple_fib") { (0..upto).map { |i| simple_fib(i) } }
  x.report("rec_fib")    { (0..upto).map { |i| rec_fib(i) } }

  x.compare!
end

(1..upto).each do |n|
  puts "#{n}: #{rec_fib(n)}"
end

bench_json.rb

require 'oj'
require 'json'
require 'pp'
require 'benchmark/ips'

hash = {
  foo: 'bar',
  baz: 100,
  baz: {
    buzz: 123,
    fizz: 'hello world'
  }
}

data = 100_000.times.reduce({}) { |h, i| h[i] = hash; h }.freeze

Benchmark.ips do |x|
  x.report("Oj.dump") { Oj.dump(data) }
  x.report("to_json") { data.to_json }

  x.compare!
end

retrieve_path_in_hash.rb

def retrieve(path, hash)
  remainder = hash.fetch(path.shift, nil)
  remainder.is_a?(Hash) ? retrieve(path, remainder) : remainder
end

path = [:foo, :bar, :baz]
hash = { foo: { bar: { baz: 123 } } }

puts "path: #{path}"
puts "hash: #{hash}"
puts "result: #{retrieve(path, hash)}"