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Function template var_string_to_int

boost::date_time::var_string_to_int — Helper function for parsing varied length strings into integers.


// In header: <boost/date_time/format_date_parser.hpp>

template<typename int_type, typename charT> 
  int_type var_string_to_int(std::istreambuf_iterator< charT > & itr, 
                             const std::istreambuf_iterator< charT > & stream_end, 
                             unsigned int max_length);


Will consume 'max_length' characters from stream only if those characters are digits. Returns '-1' if no number can be parsed. Will not parse a number preceeded by a '+' or '-'.