Is there a better PHP way for getting default value by key from array (dictionary)?

user_544463 0
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In Python one can do:

foo = {}
assert foo.get('bar', 'baz') == 'baz'

In PHP one can go for a trinary operator as in:

$foo = array();
assert( (isset($foo['bar'])) ? $foo['bar'] : 'baz' == 'baz' );

I am looking for a golf version. Can I do it shorter/better in PHP?

UPDATE [March 2020]:

assert($foo['bar'] ?? 'baz' == 'baz');

It seems that Null coalescing operator ?? is worth checking out today.

found in the comments below (+1)

language-design default-value key arrays php
8 Answers

There was a solution proposed by "Marc B" to use ternary shortcut $x = $foo ?: 'defaultvaluehere'; but it still gives notices. Probably it's a mistyping, maybe he meant ?? or it were written before PHP 7 release. According to Ternary description:

Since PHP 5.3, it is possible to leave out the middle part of the ternary operator. Expression expr1 ?: expr3 returns expr1 if expr1 evaluates to TRUE, and expr3 otherwise.

But it doesn't use isset inside and produces notices. To avoid notices better to use Null Coalescing Operator ?? which uses isset inside it. Available in PHP 7.

The expression (expr1) ?? (expr2) evaluates to expr2 if expr1 is NULL, and expr1 otherwise. In particular, this operator does not emit a notice if the left-hand side value does not exist, just like isset(). This is especially useful on array keys.

Example #5 Assigning a default value

<?php
// Example usage for: Null Coalesce Operator
$action = $_POST['action'] ?? 'default';

// The above is identical to this if/else statement
if (isset($_POST['action'])) {
    $action = $_POST['action'];
} else {
    $action = 'default';
}

?>
user_100782530
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