[antlr-interest] C++ puzzle

[yjargudo at tiscali.es]

Hello,

I think the problem is that simple_type_specifier rule of the grammar can't
parse the string "typedef typename" , because it has a different option
in the rule for each case. When antlr read "typedef" token it enters to
the typedef option but then It waits for a type and it reads "typename"
token instead.

I think that you must rewrite this rule in case that this instruction was
correct in C++.

Regards,

Yolanda


>-- Mensaje Original --
>Date: Wed, 29 Jun 2005 13:17:09 +0100
>From: David Wigg <wiggjd at lsbu.ac.uk>
>To: antlr-interest at antlr.org
>Subject: [antlr-interest] C++ puzzle
>
>
>Hi,
>
>I'm trying to parse the following extract from a C++
>preprocessed file. I wonder if someone could explain what the
>problem statement indicated might mean.
>
>#line 6 "C:\\Program Files\\Microsoft Visual Studio .NET
>2003\\VC7\\INCLUDE\\xstring"
>
>#pragma pack(push,8)
>#pragma warning(push,3)
>namespace std {
>
>#pragma warning(disable:4251)
>
>class  _String_base
>      {
>public:
>      void _Xlen() const;
>      void _Xran() const;
>      };
>
>template<class _Ty,
>      class _Alloc>
>      class _String_val
>          : public _String_base
>      {
>protected:
>      typedef typename _Alloc::template
>          rebind<_Ty>::other _Alty;    // Problem statement
>
>      _String_val(_Alty _Al = _Alty())
>          : _Alval(_Al)
>          {
>          }
>
>      _Alty _Alval;
>      };
>etc.
>
>
>I can't see how "_Alloc::template" can be a typename
>("template" is a reserved word), but what does it mean?
>
>I presume the syntax is legal but I have not been able to find
>any similar examples either in my include files in ...\Microsoft
>Visual Studio\VC98\include or in Stroustrup, Third Edition,
>Deitel & Deitel, Third Edition, or in "C++ in a Nutshell" First
>Edition.
>
>This preprocessed file was sent to me as a problem. It is
>interesting that I have not received this problem from anyone
>else.
>
>I wonder if anyone can identify the compiler and version?
>
>I also find it confusing that _Alty is a type as well as the
>name of a function and _Alval is a variable as well as the name
>of a function!
>
>Thanks,
>
>David.
>
>
>
>
>
>
>
>
>



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