On 1 December 2010 09:22, Stas Malyshev <[email protected]> wrote:
> Hi!
>
>> Its not a matter of consistency - Properties, as a cross-language concept
>> are not meant to work that way. You need to think of a property as a set
>
> Meant by whom? Is there some law of universe that prevents us from
> implementing the feature?
>
>> of two methods that just have a pretty syntax. Methods cannot be unset,
>> and nor should properties be allowed to. isset() should simply tell us
>> whether a property with the specified name is part of the class or not.
>
> If you need methods, why not use methods? If you mimick object properties,
> however, it makes sense to make them work exactly like property, otherwise
> you have to explain why they don't work this way.
>
>> isset() in the way you suggest would just be confusing. It would allow is
>> to say that a property does not exist, when in fact it does exist. This
>> is not logical.
>
> Sorry, from your answer I don't understand - what happens when you call
> isset($foo->property) and unset($foo->property)?
If we think of properties as this new entity for the language (rather
than somehow massaging existing entities to fit a new usage scenario),
then
isset($instance->property) will always return true for any defined
property. Even if the getter would return null. This is new behaviour
and can be easily documented. isset() for a property is more like
method_exists() than isset() on a variable.
With regard to unset($instance->property), from the manual ...
"The behavior of unset() inside of a function can vary depending on
what type of variable you are attempting to destroy."
So, we already have differing behaviour based upon context. Attempting
to destroy a property should through a non fatal error.
One idea I had was to keep just the get/set property methods and add
to them an additional parameter ...
<?php
public $seconds {
public set($value, $unset = False) {
if ($unset) {
// unset() has been called on the property.
// In this instance $value will be Null.
} else {
// set the property using the supplied $value.
}
},
public get($isset = False) {
if ($isset) {
// isset() has been called on the property.
// If the value is a non-destructive calculation then
maybe
returning the comparison of the result of the calculation to null.
} else {
// return the value for this property.
}
}
};
So,
isset($instance->property) would call $instance->property->get(True);
unset($instance->property) would call $instance->property->set(Null, True);
This keeps just the 2 property methods. It still allows isset/unset
and allows the developer the option of handling them.
--
Richard Quadling
Twitter : EE : Zend
@RQuadling : e-e.com/M_248814.html : bit.ly/9O8vFY
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