Question

I don’t consider myself as PHP expert but I’ve designed several pages now containing a couple of thousand lines of code each. For my current project which is for a game site I drew back on an existing function which contains the line

$M–;

Now my basic understanding of PHP tells me this doesn’t work since it should be — for short -1. But it’s not a dash, the script runs without error (error_reporting (E_ALL)) but echoing $M before and after gives me the same value.

So what does it do and why don’t I get an error?

Answer 1

That’s an en dash, which to PHP is just a random byte without specific meaning. $M–, or in UTF-8 encoding 4DE28093, is a valid variable name. Just like $漢字.

A single variable by itself just initializes that variable to null if it doesn’t already exist, the line doesn’t do anything else.