[Laszlo-user] bug trying to extend baseformitem (kind of solved)

[P T Withington]

Please file a bug at jira.openlaszlo.org.  I'm guessing the smallest  
test case would be:

<canvas>
   <attribute name="z" value="" />
</canvas>

At the very least, the compiler should give you a more informative  
message. But the question is, do you want the compiler to complain if  
you have said you want the attribute to have a value, but failed to  
give it a value (the double-quotes are not part of the value)?  Or do  
you want the compiler to assume that you didn't mean to give it a  
value after all?

Under the covers, the reason you are getting an error is what you wrote:

   <attribute name="z" value="" />

translates into the following Javascript:

   var z = ;

which is not valid.

On 2008-08-12, at 11:57EDT, Paulo Scardine wrote:

> This bug triggers only if I give a value of "", because value is an  
> 'expression' attribute.  If  I use " ' ' " or "null" it works.
>
> I still think the compiler error message is awfully misleading.
>
> Thanks,
> --
> Paulo
>
> Paulo Scardine escreveu:
>>
>> Hi all,
>>
>> I would like to send some parameters to the backend while using a  
>> form component. I tried to use dataset.setQueryParam, but soon I  
>> learned that the submit.submit() will wipe any query parameter in  
>> the dataset. The I tried to include a hidden form component in the  
>> form, something like:
>>
>> ---------8<-----------------------------------------------------
>> <canvas>
>>
>> <class name="hiddenfield" extends="baseformitem" />
>> <class name="xtd_form" extends="form">
>>   <hiddenfield name="key" value=""/>
>> </class>
>>
>> <xtd_form name="a">
>>   <statictext text="test" />
>>   <edittext width="200" name="bla" />
>> </xtd_form>
>>
>> </canvas>
>> ---------8<-----------------------------------------------------
>>
>> This will fail with:
>> ---------8<-----------------------------------------------------
>> Compilation Errors
>> Syntax error: the attribute value ended in mid-expression.
>> Look for an unclosed '(', '{', or '['.
>> ---------8<-----------------------------------------------------
>>
>> Apart from not showing any hint about the location of the offending  
>> code, the message itself is very misleading. How nasty!
>>
>> How do you guys send hidden paramenters to the backend?
>>
>> Thaks in advance,
>> --
>> Paulo
>>
>>
>>
>>
>