Re: [boost] [multi-array] compiler errors with visual studio 2012 (nfarnsworth@web.de)

27 Mar 2013

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Date: Sat, 23 Mar 2013 14:12:24 +0100 (CET)
From: nfarnsworth@web.de
To: boost@lists.boost.org
Subject: [boost] [multi-array] compiler errors with visual studio 2012
Message-ID:

Content-Type: text/plain; charset="UTF-8"
   Hello,
   have this c++ example which compiles with Visual Studio 2010 but with Visual
   Studio 2012 I got this compiler errors:
   1>------ Build started: Project: MultiArrayDemo, Configuration: Debug Win32
   ------
   1>  MultiArrayDemo.cpp
   1>d:\sandbox\multiarraydemo\multiarraydemo\multiarraydemo.cpp(11):error
   C2059: syntax error : '<'
   1>         d:\sandbox\multiarraydemo\multiarraydemo\multiarraydemo.cpp(25)
   : see reference to class template instantiation 'Data<T>' being compiled
   1>d:\sandbox\multiarraydemo\multiarraydemo\multiarraydemo.cpp(11):error
   C2238: unexpected token(s) preceding ';'
   ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========
   The example uses the boost 1.53 version. Here is the example code:
   #include "stdafx.h"
   #include 
   const int rows = 3;
   const int cols = 5;
   template<class T> struct Data
   {
    typedef boost::multi_array data_type;
    typedef typename data_type::array_view<1>::type view_type; //here is the
   first error
    typedef typename data_type::index_range range;
    Data()
    :A(boost::extents[rows][cols])
    {
      double tmp[] =
   {1.0,2.0,3.0,4.0,5.0,6.0,7.0,8.0,9.0,10.0,11.0,12.0,13.0,14.0,15.0};
      A.assign(tmp,tmp+ (rows * cols));
    }
    data_type A;
   };
   int _tmain(int argc, _TCHAR* argv[])
   {
    Data<double>* data = new Data<double>();
    Data<double>::view_type myView =
   data->A[boost::indices[0][Data<double>::range()]];
    delete data;
     return 0;
   }
   Does anybody know how to solve this problem?
   Best regards and thank you in advance
   Niklas
According to Microsoft, the code is non-conformant. Visual Studio 2010 allowed the
code to be compiled, but 2012 tightened the requirement. See:

http://msdn.microsoft.com/en-us/library/bb531344.aspx
(Second point, "Use the template keyword...", but note that they highlighted the wrong keyword).

The simple fix is to add the keyword 'template':

    typedef typename data_type::template array_view<1>::type view_type; //here is the  first error

Dan Searles