Re: Assertions

On 10/17/2013 01:49 PM, Johannes Schlüter wrote:

On Thu, 2013-10-17 at 08:25 +0100, Joe Watkins wrote:

Morning All, I'd like to draw some attention to how poor assertions are in PHP. The current assertion API is not usable in my opinion; it has a considerable overhead, relies on eval(), and is generally poorly implemented.

I don't have a strong opinion on this, but mind that by being based on eval the assert expression can use features from a different version of PHP. Something like

    if (PHP_VERSION_ID >= 50300) {
        assert('foo\\bar::baz == 42');
    }

the new form

    if (PHP_VERSION_ID >= 50300) {
        assert foo\\bar::baz == 42;
    }

would give a parse error on older versions. (Yes, I'm using 5.3 and <5.3 as example where the new form would fail anyways, feel free to use PHP_VERSION_ID >= 51200 and PHP 5.26.0 features)

         This means that assert("some code here") will pass assertion

causing no error, because strings are no longer treated as code, because eval is evil();

I think this is bad for migration of code. For one it is impossible to have a code base with asserts working in both versions. For two it silently leads to completely different behavior. Changing this needs some clever strategy allowing migration. johannes

Okay, so if the expression used is a string, it is now evaluated, this provides some backward compatibility and the possibility to avoid compilation of the expression at compile time... Better ?? Cheers Joe