unsupported std::map at() method

[Dmitry Tsarkov]

Original [issue 48](https://code.google.com/p/factplusplus/issues/detail?id=48) created by dtsarkov on 2012-03-25T21:11:51.000Z:

<b>What steps will reproduce the problem?</b> 1. Compiling Kernel under MSVC 2008 produces tSplitExpansionRules.hpp(103) : error C2039: 'at': is not a member of 'std::map' tSplitExpansionRules.hpp(108) : error C2039: 'at': is not a member of 'std::map'

<b>What version of the product are you using? On what operating system?</b> FaCT++-1.5.3, Windows XP

<b>Please provide any additional information below.</b>

ISO/IEC 14882, Second edition 2003 does not require that method at() is defined for std::map. This requirement appears only in ISO/IEC 14882 Third edition 2011. I guess that many older standard library implementations do not define std::map at(). I suggest that at() should be avoided unless the whole FaCT++ code base is transitioned to the new standard.

[Dmitry Tsarkov]

Comment [#1](https://code.google.com/p/factplusplus/issues/detail?id=48#c1) originally posted by dtsarkov on 2012-03-27T18:48:59.000Z:

Thanks, replaced everywhere with a call to operator[]