[pclasses-devel] proposed change to BaseException

[stephan b. <st...@s1...>]

Yo, again!

Having to pass a SourceInfo is pretty laestig in client code... but it 
IS a really clever idea, once you realize the P_SOURCEINFO macro is 
there to help it's not bad. However, i figure that since we HAVE the 
SourceInfo, why not USE it?

Here's a proposed change to BaseError. None of the interface changes.

The ctor prefixes the SourceInfo to the 'what' string. The result 
calling what() now includes the file, line and function name:

BaseError: piomanager.cpp:99:P::IOHandler* 
P::IOManager::findCreateHandler(const std::string&): No handler for 
protocol found.

One could argue that we shouldn't do memory allocation like this from 
BaseError, but allocation errors, and errors of that severity, happen 
via the std::exceptions, not via BaseError. Also, on Linux malloc() 
"never fails", so it's theoretically impossible to know if there is 
more memory without counting it yourself (see man malloc on a Linux 
box, in the BUGS section).

Here's the proposed code, from pexception.h:

#include <sstream>

    inline BaseError(const char* _what, const SourceInfo& _si) throw()
      : m_what(_what), m_sourceInfo(_si)
    {
            std::ostringstream os;
            os << _si.file() << ":"<<_si.line()<<":" << _si.func()<<": " 
<< _what;
            m_what = os.str();
    }

    inline const char* what() const throw()
        { return m_what.c_str(); }

    std::string m_what;

-- 
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