Well, I don't disagree as such - there's any number of (mostly bad) ways to
work around missing language features...
On Mon, May 6, 2013 at 1:12 PM, Seva Lapsha <seva.lap...@gmail.com> wrote:
> BTW, I didn't propose to wrap any use of a property reference into a meta
> object, in this case a certain distinguishable string format could
> represent it with no extra handling.
>
>
> On Mon, May 6, 2013 at 12:44 PM, Rasmus Schultz <ras...@mindplay.dk>wrote:
>
>> Seva,
>>
>> I understand that you can reference properties more consistently
>> using "{fullClassName}::{fieldName}" notation, but it's still a string, and
>> although it's now almost practically safe to assume that strings formatted
>> in that way are property-references, it still doesn't address the problem
>> in a way that is elegant or expressive.
>>
>> I don't think the Symfony component could have done a much better job
>> under the circumstances, at least not without the sacrifice of readable
>> code - typing out new PropertyReference($object, 'User::$name') sure would
>> be clunky, and not even really safe, since you can't guarantee that the
>> class-name of $object is known, and in every property-reference, the User
>> class-reference is now embedded statically in every property-reference, in
>> the form of a string.
>>
>> I think this is a good example of those times when PHP developers tend to
>> look far, far away from Java - as far away as possible - for solutions that
>> are elegant and a good fit for PHP.
>>
>> new PropertyReference($object, 'User::$name') contains two static
>> references too many, to both PropertyReference and User.
>>
>> As opposed to ^$user->name which contains the minimum amount of required
>> information - the object and property-name, nothing else.
>>
>>
>> On Mon, May 6, 2013 at 12:08 PM, Seva Lapsha <seva.lap...@gmail.com>wrote:
>>
>>> Hi Rasmus,
>>>
>>> I agree with you that strings are not the best way to refer to an
>>> element sometimes. However, to me your Symfony2 example only demonstrates
>>> the flaw of the component's design decision, not the limitation of the
>>> language. Sometimes developers (not just Symfony, but other frameworks too)
>>> don't hesitate to use contextless strings to refer to meta-data, because
>>> they underestimate the importance of keeping static referability of static
>>> entities. If they would use conventional full notation of references, e.g.
>>> "{fullClassName}::{fieldName}" in a string, this would solve your initial
>>> problem (and allow static analyzers which could be aware of the context of
>>> the framework to do their job). This is how these kind of dilemmas are
>>> solved in the world of Java for instance, where property references don't
>>> exist too.
>>>
>>> Regards,
>>> Seva
>>>
>>>
>>> On Tue, Apr 30, 2013 at 6:24 PM, Rasmus Schultz <ras...@mindplay.dk>wrote:
>>>
>>>> Any PHP dev who works with a mainstream framework does this daily, but
>>>> the
>>>> frameworks rely on strings for property-names.
>>>>
>>>> Take this example from the Symfony manual, for example:
>>>>
>>>>
>>>> class Task
>>>> {
>>>> protected $task;
>>>>
>>>> protected $dueDate;
>>>>
>>>> public function getTask()
>>>> {
>>>> return $this->task;
>>>> }
>>>> public function setTask($task)
>>>> {
>>>> $this->task = $task;
>>>> }
>>>>
>>>> public function getDueDate()
>>>> {
>>>> return $this->dueDate;
>>>> }
>>>> public function setDueDate(\DateTime $dueDate = null)
>>>> {
>>>> $this->dueDate = $dueDate;
>>>> }
>>>> }
>>>>
>>>> $form = $this->createFormBuilder($task)
>>>> ->add('task', 'text')
>>>> ->add('dueDate', 'date')
>>>> ->getForm();
>>>>
>>>> In this example, 'task' and 'dueDate' are property-references - except
>>>> of
>>>> course that, no, they're not - they're obviously just strings...
>>>> rewriting
>>>> this example to use a (fictive) form builder API with static
>>>> property-references:
>>>>
>>>> $form = $this->createFormBuilder()
>>>> ->add(^$task->task, 'text')
>>>> ->add(^$task->dueDate, 'date')
>>>> ->getForm();
>>>>
>>>> We now have static property-references, which means the codebase can be
>>>> proofed using static analysis, which also means better IDE support with
>>>> property auto-completion, inline documentation, and automatic
>>>> refactoring
>>>> for operations like renaming properties, etc.
>>>>
>>>> Note that $task need not be passed to createFormBuilder() anymore -
>>>> instead, we can now use PropertyReference::getObject() inside the
>>>> form-builder to obtain the instance.
>>>>
>>>> For that matter, we can now scrap the form-builder entirely and
>>>> introduce a
>>>> simple form-helper in the view instead:
>>>>
>>>> Task name: <?= $form->textInput(^$task->task) ?>
>>>> Due Date: <?= $form->dateInput(^$task->dueDate) ?>
>>>>
>>>> This is even better, because we now have the same level of IDE support
>>>> and
>>>> static analysis for textInput() and dateInput() which were previously
>>>> unchecked strings.
>>>>
>>>> Or even simpler:
>>>>
>>>> Task name: <?= $form->input(^$task->task) ?>
>>>> Due Date: <?= $form->input(^$task->dueDate) ?>
>>>>
>>>> Using PropertyReference::getObject() and reflection inside the
>>>> form-helper's input() method, we can now use property-annotations to
>>>> specify the input-type. This is a matter of preference of course, but
>>>> use
>>>> of annotations in Symfony is pretty popular.
>>>>
>>>> This is just one example - most PHP devs (at least those who do PHP for
>>>> a
>>>> living) use form abstractions and object/relational-mappers of some
>>>> sort,
>>>> so this has practical applications for practically everyone, everywhere.
>>>>
>>>> Rasmus Lerdorf wrote:
>>>>
>>>> It is certainly not worth overloading the XOR operator for
>>>>
>>>>
>>>> Are we really going to quibble about syntax? This adds nothing to this
>>>> discussion. And as I explained earlier, the ^ operator is used for the
>>>> sake
>>>> of discussion only - if it's more practical to use another character for
>>>> this operator, I don't care what it looks like.
>>>>
>>>>
>>>> On Tue, Apr 30, 2013 at 4:58 PM, Stas Malyshev <smalys...@sugarcrm.com
>>>> >wrote:
>>>>
>>>> > Hi!
>>>> >
>>>> > > I'm proposing we need a way to statically reference an object
>>>> property -
>>>> > > the object property itself, not it's value:
>>>> >
>>>> > You probably have use case for that, and it should be pretty easy to
>>>> > write a class that does that, but why it should be in the language? It
>>>> > certainly doesn't look like something sizeable portion of PHP devs
>>>> would
>>>> > do frequently.
>>>> >
>>>> > --
>>>> > Stanislav Malyshev, Software Architect
>>>> > SugarCRM: http://www.sugarcrm.com/
>>>> > (408)454-6900 ext. 227
>>>> >
>>>>
>>>
>>>
>>
>
