Hi Guilherme,
On Mon, Feb 9, 2015 at 1:44 PM, [email protected] <
[email protected]> wrote:
> Class invariants could be done as this example:
>
> class Foo {
> private function isValidState() {
> // Checks class's state and returns boolean
> }
>
> public function doSomething($args) {
> // Some complex operation over Foo instance using $args
> // then...
>
> assert $this->isValidState(): $this; // it would call
> Foo::__toString() for AssertionError message
> }
> }
>
> Another example of pre and post conditions:
>
> function foo($number) {
> // pre-condition
> assert is_numeric($number): '...';
>
> // Some expensive operation creating $value as response
>
> // post-condition
> assert someCheckWith($value): '...';
> return $value;
> }
>
> A good explanation about use-cases can be found here
> http://docs.oracle.com/javase/8/docs/technotes/guides/language/assert.html#class-invariants
>
Thank you for the info.
I had this syntax in mind.
class Foo {
__invariant() {
// Ignored for production.
// Check class state, every method calls invoke this method
before/after except
// __construct()/__wakeup()/__set_state() - after only
// __destruct() - before only
}
}
// Framework developer shouldn't use this. Leave this function for app
developers.
function __invariant() {
// Ignored for production.
// Invariant conditions of functions invoked for every function calls
// to check app state. e.g. global vars,etc
}
__invariant() has similar issue as __autoload(), we may be better to
provide generic registration
method.
Just my initial thought for discussion.
Regards,
--
Yasuo Ohgaki
[email protected]
