ES6 and Error Object properties

[P T Withington]

Sure would be nifty to have #file and #line directives, now that  
Javascript is the new C.

FWIW, OpenLaszlo generates annotations like so:

Filename, line, column:

/* -*- file: lpp-8534.lzx#10.7 -*- */

Same file, but line numbering needs to be reset (because output has  
more or less lines corresponding to source):

/* -*- file: #15 -*- */

No corresponding source file (i.e., generated code follows):

/* -*- file: -*- */

I can see merits to one gigantic comment up front with a mapping table  
ala Caja, but we found interspersing them worked better for humans  
staring at Javascript "assembly" in a Javascript debugger.

IWBNI @sourceurl could be expanded in some form to work with loaded  
files...

On 2009-11-04, at 14:39, Patrick Mueller wrote:

> Coincidently, I posted a blog entry on SyntaxError and eval()  
> yesterday:
>
> 	http://pmuellr.blogspot.com/2009/11/evil-eval.html
>
> On Nov 4, 2009, at 11:10 AM, Kevin Curtis wrote:
>
>> This has probably been chewed over but -
>>
>> The ES5 spec defines 'name' and 'message' as properties of the  
>> Error -
>> and ReferenceError, SyntaxError etc - objects.
>>
>> Currently engines have useful additional non-standard properties:
>> Mozilla - fileName, lineNumber and stack.
>> V8 - stack (and type, arguments). (The string returned by 'stack' is
>> not in the same format as Mozilla).
>> JSC - line, sourceId, sourceURL, expressionBeginOffset,
>> expressionCaretOffset ,expressionEndOffset - and a few others for
>> Statement errors.
>>
>>
>> Any chance for ES6 on standardizing Error object property/ies which
>> report back the error location.
>>
>> Maybe a property 'location' on the Error object which returns an  
>> object. e.g
>> e.location ->
>> {fileName:<filename>, pos: <character posNumber>, line:<lineNumber> ,
>> lineEnd:<lineNumber>, col:<colNumber> , colEnd:<colNumber>, stack:
>> <stackString>}
>>
>> With maybe pos and line being mandatory properties and the other
>> properties set if they can be set.
>>
>
> Patrick Mueller - http://muellerware.org/
>
>
>
>
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