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Rafael M. rafaelmaeuer

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  1. Download Xcode 14.3.1 via this link (you need to be signed in with your Apple Id) and install it
  2. Edit and change the Minimum System Version to 12
  3. (Optional) Do the same for (might require a restart of Xcode and/or Mac OS to make it open the simulator on run)
  4. (Optional) Replace with the one from 14.2 (or another version you have currently installed, such as 14.0).
  5. (Optional) Execute sudo xattr -cr /Applications/ if Error "Xcode is corrupted and cannot be opened"
  6. If there are problems with the simulator, reboot your Mac
var sleepSetTimeout_ctrl;
function sleep(ms) {
return new Promise(resolve => sleepSetTimeout_ctrl = setTimeout(resolve, ms));
await sleep(<duration>);
const object = {a:2, b:4, c:6, d:8};
Object.entries(object).forEach(([key, value], index) => {
console.log(`${index}: ${key} = ${value}`);
$langs = array("PHP", "JavaScript", "Python", "C++", "Ruby");
$newLangsSpace = implode(" ", $langs);
$newLangsComma = implode(", ", $langs);
$newLangsHyphen = implode("-", $langs);
// Since we are printing a string, we can use echo to display the output in the browser
echo $newLangsSpace."<br>"."<br>";
echo $newLangsComma."<br>"."<br>";
function inverse($x) {
if (!$x) {
throw new Exception('Division by zero.');
return 1/$x;
try {
echo inverse(5) . "\n";
if ($divisor == 0) {
// Other error-levels: E_USER_NOTICE, E_USER_WARNING
trigger_error("Cannot divide by zero", E_USER_ERROR);
// Turns WordPress debugging on in wp-config.php
define('WP_DEBUG', true);
// Tells WordPress to log everything to the /wp-content/debug.log file
define('WP_DEBUG_LOG', true);
// Doesn’t force the PHP 'display_errors' variable to be on
define('WP_DEBUG_DISPLAY', false);
// Hides errors from being displayed on-screen

The tests you had listed :

  • Single Parenthesis - ( ... ) is creating a subshell
  • Double Parenthesis - (( ... )) is for arithmetic operation
  • Single Square Bracket - [ ... ] is the syntax for the POSIX test
  • Double Square Brackets - [[ ... ]] is the syntax for bash conditional expressions (similar to test but more powerful)

The single bracket [ is actually an alias for the test command, it's not syntax.

One of the downsides (of many) of the single bracket is that if one or more of the operands it is trying to evaluate return an empty string, it will complain that it was expecting two operands (binary). This is why you see people do [ x$foo = x$blah ], the x guarantees that the operand will never evaluate to an empty string.

The double bracket [[ ]], on the other hand, is syntax and is much more capable than [ ]. As you found out, it does not have the "missing operand" issue and it also allows for more C-like syntax with >, <, >=, <=, !=, ==, &&, || operators.

My recommendation is the following: If your interpreter is #!/bin/bash, then always use [[ ]]

It is important to note that [[ ]] is not supported by all POSIX shells, however many shells do support it such as zsh and ksh in addition to bash