PHP array vs [ ] in method and variable declaration
PhpStandardsPhp Problem Overview
I have a question about PHP syntax.
When defining functions and variables, which convention should I use?
I know they do the same thing in practice but I would like to know which method conforms to best practice standards.
Variables
public $varname = array();
or
public $varname = [];
Methods
public function foo($bar = array()){}
or
public function foo($bar = []){}
Php Solutions
Solution 1 - Php
PSR-2 (by PHP Framework Interoperability Group) does not mention short array syntax. But as you can see in chapter 4.3 they use short array syntax to set the default value of $arg3 to be an empty array.
So for PHP >= 5.4 the short array syntax seems to be the de-facto standard. Only use array(), if you want your script to run on PHP <5.4.
Solution 2 - Php
from PHP docs:
>As of PHP 5.4 you can also use the short array syntax, which replaces array() with [].
<?php
$array = array(
"foo" => "bar",
"bar" => "foo",
);
// as of PHP 5.4
$array = [
"foo" => "bar",
"bar" => "foo",
];
?>
if you'd try using '[]' notation in earlier version than 5.4, it will fail, and PHP will throw a syntax error
for backward-compatibility you should use array() syntax.
Solution 3 - Php
just made a test to see how [] performs vs array() here is what I got
testing 1 million []s ( with $arr[] = [] )
started at : 1561298821.8754
ended at: 1561298822.6881
difference: 0.81266021728516 seconds
testing 1 million array()s ( with array_push( $arr, array()) )
started at : 1561298822.6881
ended at: 1561298823.843
difference: 1.1549289226532 seconds
testing 1 million []s ( again while the processor is hotter)
started at : 1561298823.8431
ended at: 1561298824.7448
difference: 0.9017219543457 seconds
so [] performed about 20% faster
Solution 4 - Php
That depends on what version of PHP you are targeting. For the best backward compatibility, I'd recommend you to use array(). If you don't care about older versions (< PHP 5.4), I'd recommend you to use a shorter version.