Arithmetic and NULL

[NotionCommotion]

For some reason, I though NULL and arithmetic resulted in NULL with PHP.  Maybe I was thinking JavaScript, so I tested it, but it was the same as PHP.  Then I tried MySQL, and found it was what I was thinking.  Glad I wasn't going totally crazy.

 

So....  Other than using a condition to check if null along with a ternary, what is the best way to return NULL if any of the arguments are NULL?

<?php
 
$x=null;
$y=1;
var_dump($x*$y);    //results in 0, but wanted NULL
var_dump($x+$y);    //results in 1, but wanted NULL

[Jacques1]

Just don't. Don't rely on languages to guess what you mean when you juggle with nonsense values, and don't try to produce results from nonsense input.

 

I know this is hard to believe for a PHP programmer, but many languages actually trigger an error when the program does weird things like trying to calculate sums of void values. You should do that too, because it's the most straightforward reaction. If you absolutely must produce a result, then return immediately after validation. No magic.