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From: "Dave Korn" <dave DOT korn AT artimi DOT com>
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Subject: RE: C++ name with leading underscore character not Compiling
Date: Mon, 16 Apr 2007 12:29:00 +0100
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On 16 April 2007 12:08, Václav Haisman wrote:

> Dave Korn wrote:
>> On 16 April 2007 10:34, Chelton Evans wrote:
>> 
>>> I believe it is legal to have a C++ variable name with a leading
>>>  underscore.
>> 
>>   No.  All names beginning with an underscore are reserved for the
>> implementation. 
>> 
> Nit pick, IIRC only names that start with underscore and capital letter
> or that start with double underscores are reserved. Single underscore
> and small letter should be available to users.

  Thanks for the correction.  I'm referring to the C standard; I think C++
follows basically the same rules but don't have a spec handy to refer to.
FTR, the relevant section is 7.1.3, which lists the following rules:

- All identifiers that begin with an underscore and either an uppercase letter
or another underscore are always reserved for any use.
- All identifiers that begin with an underscore are always reserved for use as
identifers with file scope in both the ordinary and tag name spaces.


    cheers,
      DaveK
-- 
Can't think of a witty .sigline today....


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