It changes the semantics. If the variable is set to a falsey value and ?:
uses an implicit isset, the value of the expression will be the falsey
value.
$config['width'] = ''
$width = $config['width'] ?: 300
# $width == ''
If !empty were used instead of isset, you could preserve semantics ($a ?:
dflt = !empty($a) ? $a : dflt).
Since this has been discussed before, here's a previous solution with zero
of those problems:
// A new operator.
$width = $config['width'] ?? 300;
// Actual behavior of the operator in pseudo code:
$width = isset($config['width']) ? $config['width'] : 300;
Why wasn't it implemented? No reason, it just wasn't. But people keep asking
about it, so it's only a matter of time.
Stan
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
