olleharstedt

module Typestate

open FStar.Heap
open FStar.ST

type state = 
  | Open
  | Closed

type file = {

olleharstedt

<?php

$command = sprintf(
    'echo -e "%s" | nc -U /var/run/docker.sock',
    'GET /info HTTP/1.1\r\nHost: localhost\r\n'
);
echo '<pre>'; var_dump($command); echo '</pre>';
var_dump(exec($command));

olleharstedt

<?php

$command = sprintf(
    'echo -e "%s" | nc -U /var/run/docker.sock',
    "GET /info HTTP/1.1\r\nHost: localhost\r\n"
);
echo '<pre>'; var_dump($command); echo '</pre>';
var_dump(exec($command));

olleharstedt

<?php

$command = sprintf(
    'echo -e "%s" | nc -U /var/run/docker.sock',
    "GET /info HTTP/1.1\r\nHost: localhost\r\n"
);
echo '<pre>'; var_dump($command); echo '</pre>';
var_dump(exec($command));

olleharstedt

<?php

$command = sprintf(
    'echo -e "%s" | nc -U /var/run/docker.sock',
    "GET /info HTTP/1.1\r\nHost: localhost\r\n\r\n"
);
echo '<pre>'; var_dump($command); echo '</pre>';
var_dump(exec($command));

olleharstedt

<?php

error_reporting(E_ALL);
set_time_limit(0);
ob_implicit_flush();

$sock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

if (socket_bind($sock, '127.0.0.10', 888) === false) {
    die('cannot bind' . PHP_EOL);

olleharstedt

<?php

require __DIR__ . '/../vendor/autoload.php';

use Amp\Http\Client\HttpClientBuilder;
use Amp\Http\Client\Request;
use Amp\Loop;
use Amp\ByteStream\ClosedException;
use Amp\File;

olleharstedt

<?php

require __DIR__ . '/../vendor/autoload.php';

use Amp\Http\Client\HttpClientBuilder;
use Amp\Http\Client\Request;
use Amp\Http\Client\HttpClient;
use Amp\Loop;
use Amp\ByteStream\ClosedException;
use Amp\File\File;

olleharstedt

class Query {
    constructor() {
        this.select = '';
        this.from = '';
        this.where = '';
    }
}

for (let i = 0; i < 1000000; i++) {
    const q = new Query();

olleharstedt

Pre-req: Functional core, imperative shell

Pre-req: Side-effects, purity, referential transparency

• The functional core is more testable and more composable than the imperative shell or effectful code
• Extending the functional core means making a bigger part of the software pure
• Side-effects can in some cases easily be lifted out from a function, creating a more composable and testable unit
• But sometimes, side-effects are tangled in business logic
• Some side-effects can be delayed until end of request (e.g., updating user's name in database; exception at failure can still be thrown)
• Example: Create dummy users