I just tried to see if it might work, but I get an error. Obviously that’s a
no-no...
[java]
/Users/harbs/Documents/ApacheFlex/flex-asjs/frameworks/projects/XML/src/main/flex/XML.as(317):
col: 13 A return value is not allowed in a constructor.
[java]
[java] return (xml as XMLList).toXML();
> On Jul 17, 2017, at 10:28 PM, Harbs <[email protected]> wrote:
>
> I don’t think so. Write one where? How? We already have a top level XML
> constructor.
>
> Wouldn’t the compiler output:
> XML(myXML)
>
> as:
> org.apache.flex.utils.Language.as(myXML,XML)?
>
> I’m pretty sure the only way to instantiate an XML object is to use new.
>
> Well, I just tried XML(myXMLList) and it does not call Language.as. It keeps
> the code exactly as it was and invokes the XML constructor with the XMLList
> as the parameter.
>
> Of course that goes totally haywire this refers to window and none of the
> code makes any sense. I have no idea if a constructor can return something
> else in the middle of it. (i.e. if an XMLList is fed to the XML constructor,
> call toXML() on the XMLList and return that.)
>
> Harbs
>
>> On Jul 17, 2017, at 10:08 PM, Alex Harui <[email protected]> wrote:
>>
>> I thought we (you) already wrote one. If not, we won't we need one?
>>
>> -Alex
>>
>> On 7/17/17, 12:01 PM, "Harbs" <[email protected]> wrote:
>>
>>> Thanks for the pointer.
>>>
>>> I changed the emitter to output indexed access. It seems to work. :-)
>>> (committed)
>>>
>>> I’m not sure what you mean about the top level XML function. How does
>>> that work in Javascript?
>>>
>>>> On Jul 17, 2017, at 7:47 PM, Alex Harui <[email protected]>
>>>> wrote:
>>>>
>>>> You can try #2 by changing ForEachEmitter.java.
>>>>
>>>> For the general problem, we should probably just use the XML() top-level
>>>> function to "coerce" XMLList to XML.
>>>>
>>>> My 2 cents,
>>>> -Alex
>>>>
>>>> On 7/17/17, 9:23 AM, "Harbs" <[email protected]> wrote:
>>>>
>>>>> That is a fourth option.
>>>>>
>>>>> In terms of overhead, option #2 is probably cheapest and option #4 is
>>>>> probably most expensive.
>>>>>
>>>>> What’s the difference in terms of difficulty of changing the compiler?
>>>>>
>>>>> I agree with the general problem. It could be that we should to a
>>>>> function to XMLList toXML() (or something like that) where it would
>>>>> return an XML element if it’s a single and throw an error otherwise.
>>>>> Then
>>>>> anytime there is an XMLList assignment to XML, the compiler could add
>>>>> .toXML().
>>>>>
>>>>> Harbs
>>>>>
>>>>>> On Jul 17, 2017, at 7:11 PM, Alex Harui <[email protected]>
>>>>>> wrote:
>>>>>>
>>>>>> IMO, this points out a generic problem where in ActionScript:
>>>>>>
>>>>>> var harbs:XML = SomeXMLListWithOneElement;
>>>>>>
>>>>>> would auto-coerce the XMLList to XML by grabbing the one element. So
>>>>>> we
>>>>>> have to deal with that some day. But there is probably a quick fix in
>>>>>> the
>>>>>> generated code for "for each" where we just generate:
>>>>>>
>>>>>> var foo = foreachiter57_target.child(foreachiter57)[0];
>>>>>>
>>>>>>
>>>>>> Thoughts?
>>>>>> -Alex
>>>>>>
>>>>>> On 7/17/17, 3:40 AM, "Harbs" <[email protected]> wrote:
>>>>>>
>>>>>>> I discovered an issue with “for each” in the XML classes:
>>>>>>>
>>>>>>> Currently, for each does the following:
>>>>>>>
>>>>>>> The following AS code:
>>>>>>>
>>>>>>> var fooList:XMLList = getFooList();
>>>>>>> for each(var foo:XML in fooList){
>>>>>>> doSomethingWithFoo(foo);
>>>>>>> }
>>>>>>>
>>>>>>> outputs the following JS:
>>>>>>>
>>>>>>> var /** @type {XMLList} */ fooList = this.getFooList();
>>>>>>> var foreachiter57_target = fooList;
>>>>>>> for (var foreachiter57 in foreachiter57_target.elementNames())
>>>>>>> {
>>>>>>> var foo = foreachiter57_target.child(foreachiter57);
>>>>>>> {
>>>>>>> this.doSomethingWithFoo(foo);
>>>>>>> }}
>>>>>>>
>>>>>>> The problem is with the line:
>>>>>>> var foo = foreachiter57_target.child(foreachiter57);
>>>>>>>
>>>>>>> foo should be of type XML. According to the ECMA spec for E4X,
>>>>>>> XML.prototype.child and XMLList.prototype.child both ALWAYS return an
>>>>>>> XMLList and not an XML object. This is true even if the argument fed
>>>>>>> into
>>>>>>> child is an integer. So myXMLList.child(“0”) will return an XMLList
>>>>>>> with
>>>>>>> one XML element which is the first element of the original XMLList.
>>>>>>> We
>>>>>>> need the actual XML object at the specified index without the XMLList
>>>>>>> wrapper.
>>>>>>>
>>>>>>> There are three ways I can see to fix this problem:
>>>>>>>
>>>>>>> 1. Ignore the spec and return an XML object when the argument is an
>>>>>>> integer.
>>>>>>> 2. Change the compiler output to: var foo =
>>>>>>> foreachiter57_target[foreachiter57]; Bracket access to XMLList
>>>>>>> returns
>>>>>>> an
>>>>>>> XML object.
>>>>>>> 3. Add a new function to use instead of child() (i.e. getChild()).
>>>>>>>
>>>>>>> Thoughts?
>>>>>>>
>>>>>>> Harbs
>>>>>>
>>>>>
>>>>
>>>
>>
>
