Subj : Re: ++0 is not a syntax error?
To   : Brendan Eich
From : Igor Bukanov
Date : Wed Aug 18 2004 07:03 pm

Brendan Eich wrote:
> Igor Bukanov wrote:
> 
>> Hi!
>>
>> As far as I can see ECMAScript requires that ++0 should produce 
>> RuntimeError, not SyntaxError. So, for example, the following should 
>> be OK:
>>
>> var f = Function('++0')
>>
>> and only during call to f RuntimeError should be generated. Microsoft 
>> JScript and KDE JavaScript implementation follows this while 
>> SpiderMonkey behaves much saner IMO and report SyntaxError during 
>> parsing. But does ECMA-267 allow this early error reporting?
>>
>> Regards, Igor
> 
> 
> 
> Yes, explicitly so, per Section 16 of ECMA-262 Edition 3:

Thanks, I missed that. I will make Rhino to match SM in this respect.

While changing Rhino parser to allow to use native functions  as 
left-hand-side expressions in Rhino, I assumed that bad left hand side 
should always be a runtime error and added a few lines of code to handle 
that. But those comments in the standard allows to remove those lines 
and make Rhino as JS syntax checker to work better.

Regards, Igor

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