PHP shorthand syntax

Question

I\'ve just came across this on GitHub.

 ($config === NULL) and $config = Kohana::config(\'email\');

Is that the equivalent of

Answer 1

Took me a second to get it, but that should actually work in just about every programming language. Because the "and" or "or" operators are lazily evaluated, if the statement on the left is false, then there's no need to evaluate the rest of the statements because the whole expression will always be false (false and true is false). Likewise, you can do it with "or", but the statement on the left would have to be true, then the one on the right wouldn't be evaluated.

PS: It doesn't really matter in this case that what's on the right isn't really a boolean expression; it'll just take on the truth value of $config

Answer 2

AND is a PHP logical operator.

($config === NULL) and $config = Kohana::config('email');

has equivalent outcome (but has a lesser operator precedence) to

($config === NULL) && $config = Kohana::config('email');

Personally, to avoid any confusion I would use your second approach.