Why Continuous Syntax Checking Matters

Today, I ran into a great example of why continuous syntax checking matters. Now, I understand that some of the slowness that I experienced in diagnosing this problem is because I'm still getting used to C++ and Boost and the resulting error messages. but still...

Here's the relevant chunk of code with the error in bold and line 69 pointed out for future reference.


--> Line 69

boost::program_options::options_description config( "Config File Options ");
config.add_options()
( "currentTime", boost::program_options::value()->default_value(defaultDateString), "YYYY-MM-DD HH:MM:SS" )
( "df", boost::program_options::value(), "description" )
( "debugDir", boost::program_options::value(), "location for log file" )
( "workingDir", boost::program_options::value(), "all intermediate files will go here" )
( "script", boost::program_options::value(), "script directory (location of func)" )
( "DBName", boost::program_options::value<std::string()>(), "name of database" )
( "DBUserName", boost::program_options::value< std::string >(), "username for database" )
( "DBPassword", boost::program_options::value< std::string >(), "password for database" )
( "DBSchema", boost::program_options::value(), "schema to be used for database" )
( "ASchema", boost::program_options::value(), "schema to access A tables" )
( "PSchema", boost::program_options::value(), "schema to access P tables" )
( "opsEmail", boost::program_options::value(), "operations email address" )
( "researchEmail", boost::program_options::value(), "research email address" );



And I'll just add the error message afterwards, for your enjoyment. I won't belabor the point by actually writing anything afterwards. I think it will be pretty clear. If I had had some kind of auto-syntax checking active, then this would have been a lot easier to find. Probably would have saved 5 minutes of staring at the code and 15 minutes of entering a blog to bitch about it. That's a 20 point swing!

/usr/include/boost/program_options/detail/value_semantic.hpp: In member function `void boost::program_options::typed_value::notify(const boost::any&) const [with T = std::string ()(), charT = char]':
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/program_options/detail/value_semantic.hpp:28: error: function return type cannot be function
/usr/include/boost/program_options/detail/value_semantic.hpp:28: error: function return type cannot be function
/usr/include/boost/any.hpp:172: error: function return type cannot be function
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/program_options/detail/value_semantic.hpp:30: error: assignment of read-only location
/usr/include/boost/program_options/detail/value_semantic.hpp:30: error: cannot convert `std::string ()()' to `std::string ()()' in assignment
/usr/include/boost/program_options/detail/value_semantic.hpp: In function `void boost::program_options::validate(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&, T*, long int) [with T = std::string ()(), charT = char]':
/usr/include/boost/program_options/detail/value_semantic.hpp:149: instantiated from `void boost::program_options::typed_value::xparse(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/program_options/detail/value_semantic.hpp:81: error: function return type cannot be function
/usr/include/boost/program_options/detail/value_semantic.hpp:81: error: function return type cannot be function
/usr/include/boost/lexical_cast.hpp:185: error: function return type cannot be function
/usr/include/boost/any.hpp: At global scope:
/usr/include/boost/any.hpp: In instantiation of `boost::any::holder':
/usr/include/boost/any.hpp:159: instantiated from `ValueType* boost::any_cast(boost::any*) [with ValueType = std::string ()()]'
/usr/include/boost/any.hpp:167: instantiated from `const ValueType* boost::any_cast(const boost::any*) [with ValueType = std::string ()()]'
/usr/include/boost/program_options/detail/value_semantic.hpp:28: instantiated from `void boost::program_options::typed_value::notify(const boost::any&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/any.hpp:125: error: field `boost::any::holder::held' invalidly declared function type
/usr/include/boost/any.hpp: In function `ValueType* boost::any_cast(boost::any*) [with ValueType = std::string ()()]':
/usr/include/boost/any.hpp:167: instantiated from `const ValueType* boost::any_cast(const boost::any*) [with ValueType = std::string ()()]'
/usr/include/boost/program_options/detail/value_semantic.hpp:28: instantiated from `void boost::program_options::typed_value::notify(const boost::any&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/any.hpp:159: error: cannot convert `std::string (**)()' to `std::string (*)()' in return
/usr/include/boost/lexical_cast.hpp: In function `Target boost::lexical_cast(Source) [with Target = std::string ()(), Source = std::basic_string, std::allocator >]':
/usr/include/boost/program_options/detail/value_semantic.hpp:81: instantiated from `void boost::program_options::validate(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&, T*, long int) [with T = std::string ()(), charT = char]'
/usr/include/boost/program_options/detail/value_semantic.hpp:149: instantiated from `void boost::program_options::typed_value::xparse(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/lexical_cast.hpp:185: error: function return type cannot be function
/usr/include/boost/program_options/detail/value_semantic.hpp:81: instantiated from `void boost::program_options::validate(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&, T*, long int) [with T = std::string ()(), charT = char]'
/usr/include/boost/program_options/detail/value_semantic.hpp:149: instantiated from `void boost::program_options::typed_value::xparse(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/lexical_cast.hpp:191: error: invalid conversion from `std::string (*)()' to `int'
/usr/include/boost/lexical_cast.hpp:187: warning: address of local variable `result' returned
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits: At global scope:
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits: In instantiation of `std::numeric_limits':
/usr/include/boost/lexical_cast.hpp:131: instantiated from `boost::detail::lexical_stream::lexical_stream() [with Target = std::string ()(), Source = std::basic_string, std::allocator >]'
/usr/include/boost/lexical_cast.hpp:186: instantiated from `Target boost::lexical_cast(Source) [with Target = std::string ()(), Source = std::basic_string, std::allocator >]'
/usr/include/boost/program_options/detail/value_semantic.hpp:81: instantiated from `void boost::program_options::validate(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&, T*, long int) [with T = std::string ()(), charT = char]'
/usr/include/boost/program_options/detail/value_semantic.hpp:149: instantiated from `void boost::program_options::typed_value::xparse(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:290: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:292: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:295: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:297: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:299: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:301: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:304: error: function return type cannot be function
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/limits:308: error: function return type cannot be function
/usr/include/boost/lexical_cast.hpp: In member function `bool boost::detail::lexical_stream::operator>>(InputStreamable&) [with InputStreamable = std::string ()(), Target = std::string ()(), Source = std::basic_string, std::allocator >]':
/usr/include/boost/lexical_cast.hpp:189: instantiated from `Target boost::lexical_cast(Source) [with Target = std::string ()(), Source = std::basic_string, std::allocator >]'
/usr/include/boost/program_options/detail/value_semantic.hpp:81: instantiated from `void boost::program_options::validate(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&, T*, long int) [with T = std::string ()(), charT = char]'
/usr/include/boost/program_options/detail/value_semantic.hpp:149: instantiated from `void boost::program_options::typed_value::xparse(boost::any&, const std::vector, std::allocator<_T2> >, std::allocator, std::allocator<_T2> > > >&) const [with T = std::string ()(), charT = char]'
private/SVCExecutable.cpp:69: instantiated from here
/usr/include/boost/lexical_cast.hpp:149: error: ambiguous overload for 'operator>>' in '((boost::detail::lexical_stream, std::allocator > >*)this)->boost::detail::lexical_stream, std::allocator > >::stream >> output'
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/istream.tcc:87: note: candidates are: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>&(*)(std::basic_istream<_CharT, _Traits>&)) [with _CharT = char, _Traits = std::char_traits]
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/istream.tcc:93: note: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_ios<_CharT, _Traits>&(*)(std::basic_ios<_CharT, _Traits>&)) [with _CharT = char, _Traits = std::char_traits]
/usr/lib/gcc/i386-redhat-linux/3.4.5/../../../../include/c++/3.4.5/bits/istream.tcc:102: note: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base&(*)(std::ios_base&)) [with _CharT = char, _Traits = std::char_traits]
make[1]: *** [debug.obj/SVCExecutable.o] Error 1
make[1]: Leaving directory `/data/aykroyd/cvs/Optimization/five0/PredictionAndBidding/SegmentVolumeCalculator'
make: *** [default] Error 2
make: Leaving directory `/data/aykroyd/cvs/Optimization/five0/PredictionAndBidding/SegmentVolumeCalculator'
exit
Connection to master closed.

exit

Compilation exited abnormally with code 2 at Thu Jul 26 10:53:43