On 2 December 2010 13:51, <presid...@basnetworks.net> wrote:
>> 2010/12/1 Richard Quadling <rquadl...@gmail.com>
>>
>>> On 1 December 2010 09:22, Stas Malyshev <smalys...@sugarcrm.com> wrote:
> ...
>
>> Why change the expected behavior of isset? If a property has not been set
>> then isset must return false, and that includes $foo->name = NULL.
>
>
> Thats simple then, when isset is invoked, call the get method, and if it
> returns null then isset() returns false, but otherwise returns true. That
> was likely just a small oversight on Richard's part.
No, it was not an oversight.
Calling the getter() in response to isset() will probably result in a
change to the value of the property. For a property, isset() can and
only be interested in the last value of the property, not the next
value.
As I understand things, isset() performs 2 tests. First a check to see
if the variable exists and then to see if it has a value assigned.
For a property, the first part of that equation is fairly simple - the
property has to exist or not.
The second part though is not easy. A variable will not change value
in response to isset(), but, if isset() calls the getter(), then it
could and probably would. Calling isset() shouldn't alter anything.
Having isset() call the getter() and unset() call the setter() is fine
as long as the getter() and setter() know why they are being called.
If the developer needs to supply the last value - their choice - then
this could be implemented by caching the last value in a local scope
static. Completely encapsulated.
get($isset = false){
static $lastValue;
if (!$isset) {
// Generate the new value and assign it to $lastValue
}
return $lastValue;
}
Richard.
--
Richard Quadling
Twitter : EE : Zend
@RQuadling : e-e.com/M_248814.html : bit.ly/9O8vFY
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