v-kolesnikov

# typed: strict
# frozen_string_literal: true

require "base32"
require "securerandom"
require "ulid"

# A type to represent UUIDs. Particularly useful for annotating fields in API
# representations or Sorbet parameters to help prevent accidentally mixing up
# UUIDs and EIDs as they're being passed around as loose strings.

v-kolesnikov

Super fast, keyboard-optimized, client side Hugo search

This is a fork of and builds upon the work of Eddie Webb's search and Matthew Daly's search explorations.

It's built for the Hugo static site generator, but could be adopted to function with any json index compatible with Fuse fuzzy search library.

To see it in action, go to craigmod.com and press CMD-/ and start typing.

v-kolesnikov

HTTP Streaming (or Chunked vs Store & Forward)

The standard way of understanding the HTTP protocol is via the request reply pattern. Each HTTP transaction consists of a finitely bounded HTTP request and a finitely bounded HTTP response.

However it's also possible for both parts of an HTTP 1.1 transaction to stream their possibly infinitely bounded data. The advantages is that the sender can send data that is beyond the sender's memory limit, and the receiver can act on

v-kolesnikov

require 'openssl'
require 'base64'

# ===== \/ sign =====
# generate keys
key = OpenSSL::PKey::EC.new("secp256k1")
key.generate_key
public_key = key.public_key
public_key_hex = public_key.to_bn.to_s(16).downcase # public key in hex format

v-kolesnikov

list:
  - name:       Adobe Systems
    name2:      Adobe Systems Inc.
    url:        http://www.adobe.com
    symbol:     ADBE
    price:      39.26
    change:     0.13
    ratio:      0.33
  - name:       Advanced Micro Devices
    name2:      Advanced Micro Devices Inc.

v-kolesnikov

Latency Comparison Numbers
--------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

v-kolesnikov

LLDB Cheat Sheet

A complete gdb to lldb command map.

Print out

• Print object

(lldb) po responseObject
(lldb) po [responseObject objectForKey@"state"]

• p - Print primitive type

v-kolesnikov

class Jobs < ROM::Relation[:sql]
  schema(:jobs) do
    # ...

    associations do
      belongs_to :team
      belongs_to :template
      belongs_to :address
      belongs_to :client
    end

v-kolesnikov

Строгость и нищета списков.

Map и структурная рекурсия.

Применить функцию к каждому элементу списка - это просто: ###GHC/Base.lhs

map _ []     = []
map f (x:xs) = f x : map f xs

v-kolesnikov

require 'dry-validation'

class EnvValidation
  class ENV
    def inspect
      ivs = instance_variables.each { |v| "#{v}=#{instance_variable_get(v)}" }.join(', ')
      "ENV[#{ivs}]"
    end

    def to_s