> On 20 Sep 2023, at 03:03, Niels Dossche wrote:
>
> Hi Stephen
>
> On 19/09/2023 09:58, Stephen Reay wrote:
>>
>>
>>> On 19 Sep 2023, at 14:30, Tim Düsterhus wrote:
>>>
>>> Hi
>>>
>>> On 9/19/23 08:35, Stephen Reay wrote:
Regarding the private constructor: I understand the issue with the *old*
class being confusing - but your new class doesn't have that issue,
because there are no "loadXXX" methods: as you said, if you're loading an
existing document, you're forced to do it via the static factory methods.
With that change alone, there's zero risk of confusion in allowing direct
constructor calls, because once the object is instantiated there is no
subsequent way to load a document and inadvertently change the encoding.
Having a regular constructor and then one or more factory methods for
specific cases is already a concept in PHP (i.e. DateTime[Immutable]'s
`createFromXXX` as well as a constructor), and IMO needing to call a
factory method to get an "empty" document seems out of place in PHP - it
seems a bit like a Java-ism - using a factory, where one just isn't
required.
>>>
>>> I was one of the persons who discussed this updated API with Niels in
>>> private and looking up the discussion it was me who proposed making the
>>> constructor private and just providing named constructors.
>>>
>>> From the perspective of the user of the API, I like the symmetry between
>>> all the named constructors:
>>>
>>> Whenever I want to create a new document, I use one of the fromXyz()
>>> methods. And when I use those, I get exactly what it says on the tin.
>>>
>>> Making the regular constructor available for use would effectively make
>>> whatever that constructor does a special case / the default case. This
>>> makes sense for DateTimeImmutable, because the __construct() variant is
>>> likely much more often used than the various createFromXyz() variants. For
>>> the HtmlDocument I find it less obvious that creating an empty document
>>> would be the default case compared to loading an existing document from a
>>> file.
>>>
>>> We should probably rename the named constructors to include the "create"
>>> prefix for consistency with DTI though.
>>>
>>> Best regards
>>> Tim Düsterhus
>>>
>>
>> Hi Tim,
>>
>>
>> Thanks for providing context on where this idea came from.
>>
>>
>> The constructor + specialised factory methods pattern is not exactly new in
>> PHP (e.g. it took about 3 minutes to find multiple Symphony classes doing
>> this), and disabling the public constructor for purely cosmetic reasons
>> sounds like a very weird, and ironic choice to me, when the stated goal is
>> to make the API *less surprising* than the previous one.
>>
>
> Besides the points that have been mentioned by Tim and Larry, there's also
> the expectation of the programmer that migrates to the new classes to take
> into account.
> They're used to calling the constructor on the old class and calling a load
> method afterwards.
> As there is still a constructor, but no load method, this might be confusing
> for them.
> So in my opinion, disabling it makes it less surprising than the previous one.
> Also, just because Symfony does this doesn't mean it's automatically
> something we should follow.
>
>>
>> Cheers
>>
>> Stephen
>
> Kind regards
> Niels
>
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Hi Niels, Larry
To clarify my earlier message about having the factory methods on the
faux-interface - when I said meta programming that was probably the wrong term
to use, so I apologise for the confusion.
It's true that the *developer* needs to know the expected type of the string
being parsed. It's not true that the code directly invoking the 'fromString'
method necessarily needs to know - passing classnames as a string and calling
static methods on the string is also an established concept in PHP, which works
really well when the method being called is defined on a single top-level class
or interface.
A real world example I had in mind, is a Request (e.g. a curl request, or some
other http-fetching) class that can decode responses into native PHP objects,
with options for the callee to define the object type that's wanted; with just
the two provided classes there's already double the checks required to know if
the specified class name is one the library knows how to use. If a hypothetical
class to handle SVG, RSS, ODF (or any other specialised use of XML) class uses
the faux-interface from this RFC as it's base, there's no way for the Request
class to know that it can instantiate an instance from a string, without
falling back to method_exists() checks.
The only reason I mentioned the DateTime or Symphony classes at all, is to
highlight that people have been using classes with a regular constructor, and
one or more static factory
