TypeError: I could use some explanation

[Sundararajan Athijegannathan]

Actually, it'd be difficult for us to debug as well. As I said, most 
likely your Java Map passed is being treated as a (JS) script object - 
and it is not. Please note that Nashorn uses wrapperless Java objects 
with scripts - so scripts see the exposed Java objects as plain Java 
objects. So, the solution would be to use an actual script object in 
such cases.

-Sundar

On 12/16/2015 8:52 PM, Kasmeroglu, Daniel wrote:
> On Mi, 2015-12-16 at 20:11 +0530, Sundararajan Athijegannathan wrote:
>> If the script function t4 expects that "t4_context" is a script object
>> and so calls Object.prototype function or any JS function that expects
>> "this" to be a script object, you'll get a TypeError (per spec.).  We
>> need bit more information on the code of "t4" to help further.
>>
> The code of 't4' is a problem here as it's generated by Handlebars. It's
> ScriptObjectMirror presentation results in:
>
> --8>--
> [_setup -> function (setupOptions) {
> 	    if (!compiled) {
> 	      compiled = compileInput();
> 	    }
> 	    return compiled._setup(setupOptions);
> 	  }]
> [_child -> function (i, data, blockParams, depths) {
> 	    if (!compiled) {
> 	      compiled = compileInput();
> 	    }
> 	    return compiled._child(i, data, blockParams, depths);
>   }]
> --<8--
>
> However I don't expect anyone to investigate this code further as I
> think this might require quite a bit of work
> (https://github.com/wycats/handlebars.js/tree/master). It's essentially
> a template which will render it's content with the supplied hash in
> question.
>
> Last but not least I figured out a workaround which seem to work fine.
> I'm simply adding the entries of the map 't4_context' and I'm generating
> the template function call accordingly. F.e.
>
>> t4(t4_context)
> turns into
>
>> t4({'assets': assets, 'def': def})
> Nevertheless if someone knows an answer to the problem it would be nice
> to know.
>
>
>
>> -Sundar
>>
>> On 12/16/2015 7:31 PM, Kasmeroglu, Daniel wrote:
>>> Hi there,
>>>
>>> First of all: thanks for the great work with Nashorn.
>>> Unfortunately I'm currently a little bit stuck as I don't get what I'm
>>> doing wrong here.
>>> Here's a simple code snippet that explains what I'm doing:
>>>
>>> --<8--
>>> ScriptEngine engine = ...
>>> Map<String, Object> context = ...
>>> engine.put("t4_context", context);
>>> engine.eval("t4(t4_context);");
>>> --8>--
>>>
>>> The variable 't4' is a compiled template generated through Handlebars
>>> (so it's a function taking a hash).
>>> Unfortunately I don't get it running as there's the following complain:
>>>
>>> --<8--
>>> Caused by: <function>:30 TypeError: {assets=dodo} is not an Object
>>> --8>--
>>>
>>> It's clear to me that the issue is caused since the java object
>>> 'context' isn't an instance of 'ScriptObject'. However it isn't clear to
>>> me why this happens.
>>>
>>> It would be nice to give me a hint of what I'm doing wrong or to point
>>> me to some helpful documentation.
>>>
>>> Thanks in advance.
>>>
>>>