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Date: Wed, 29 Jan 2014 22:13:28 +0000
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Subject: Re: [PHP-DEV] DbC for PHP?
From: rowan.collins@gmail.com (Rowan Collins)

On 28/01/2014 11:05, Alexander Lisachenko wrote:
> Here is my one-minute implementation with Go! AOP framework.
[...]
>
> class Test
> {
>      /**
>       * @Contract("strlen($foo) > 6")
>       */
>      public function bar($foo)
>      {
>          echo $foo;
>      }
> }

So, dozens of lines of boilerplate, Reflection, and other obscure 
features (including, presumably, a userland implementation of 
annotations) and the end result is ... an assertion. The pre-condition 
is not being added as an aspect, it's hard-coded right there next to the 
function, doing exactly the same thing as adding this single line at the 
top of the function:

assert('strlen($foo) > 6');

Post-conditions are a little trickier: they require a 
single-point-of-return (something which has its advocates anyway, and 
could easily be enforced as a project coding standard) and potentially 
introduce an intermediate variable that could otherwise be skipped. But 
this seems like a lot of overhead to work around that.

Now, I realise that this was a simple example, but I would be interested 
to see what such an approach could actually offer in return for its 
complexity.

Regards,

-- 
Rowan Collins
[IMSoP]