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v = new Set(); do { v.add(Math.floor(Math.random() * 60) + 1) } while(v.size < 6); v

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({ HFS }) => async (state = {}, update = {}) => {
  const { price, mts } = update
  const position = HFS.getPosition(state)

  if (position) {
    return HFS.closePositionMarket(state, { price, mtsCreate: mts })
  }

  return HFS.openLongPositionMarket(state, {
    mtsCreate: mts,

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• team knowledge
  • number of team-members and knowledge scoring for each member (beginner/intermediate/expert)
  • integrations with other teams?
  • N/A
• goal/type
  • web? cli? database connectors? gui? mobile?
• reuse of code
  • is there any legacy code that must be used?
  • rewrite cost?
• language interop (JVM, native bindings)

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Foundation:

1. Descomplicando CQRS
2. Descomplicando Event Sourcing
3. DDD do jeito certo

Types of implementation:

• Event Sourcing You are doing it wrong

Learning more:

• The Many Meanings of Event-Driven Architecture

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#include <sys/mman.h>
#include <fcntl.h>

unsigned char* shared(const char* path) {
  int fd = open(path, O_RDWR | O_CREAT, (mode_t) 0600); 
  posix_fallocate(fd, 0, 65536);
  return (unsigned char*) mmap(0, 65536, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0); 
}

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// double 12345.67 -> int 1234567

struct Trie {
  std::array<int, (size_t) 1.1e7> cnt, sum;

  void update(int price, int qty) {
    int cnt_delta = qty ? (cnt[price] ? 0 : +1) : (cnt[price] ? -1 : 0);
    int sum_delta = qty - sum[price];
    for (int node = 0, tmp = price, p10 = 1e7; p10; tmp %= p10, p10 /= 10) {
      node = 10 * node + tmp / p10;

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package main

import (
	"fmt"
	"sync"
)

func TrySend[T any](ch chan T, item T) bool {
	select {
	case ch <- item:

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const { ul, li } = require('./html')

const list = ul({ title: 'awesome list' },
  li({ title: 'interactive', onclick: () => alert(1) }, 'first'),
  li('second')
)

document.body.appendChild(list)

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• Always do smart step into
• Do not step into library scripts
• Do not step into scripts:

• /home/<USER>/.config/JetBrains/WebStorm2021.1/javascript/nodejs/**
• node:internal/*
• /**

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Try/Catch

AVOID USING TRY/CATCH FOR FLOW CONTROL!!!!

• https://softwareengineering.stackexchange.com/a/107760
• https://web.archive.org/web/20140430044213/http://c2.com/cgi-bin/wiki?DontUseExceptionsForFlowControl

If you don't know what to do with it, handle it in a decent manner at least:

• https://digitaldrummerj.me/dont-swallow-the-exceptions/

It is also a costy abstraction when comes to a performance point of view in most languages: