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From: "Christoph M. Becker" <cmbecker69@arcor.de>
Newsgroups: comp.lang.javascript
Subject: Re: ! function
Date: Fri, 08 May 2015 00:26:16 +0200
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Xref: csiph.com comp.lang.javascript:27562

I wrote:

> Evertjan. wrote:
> 
> 
>> But why does this work:
>>
>> -function(a){alert(a);return 2}('hi')
>>
>> and this does not:
>>
>> function(a){alert(a);return -2}('hi')
>>
>> ??
> 
> while the second line is parsed as (again simplified)
> 
>   SourceElement -> FunctionDeclaration -> ...
> 
> and the remaining ('hi') is a syntax error, as no ASI applies here.

That's wrong.  According to ES 5.1 the line can't be parsed as
FunctionDeclaration, because the Identifier is missing.  Actually, the
code doesn't match any production, and as such is syntactically invalid.

-- 
Christoph M. Becker