boost/program_options/detail/value_semantic.hpp
// Copyright Vladimir Prus 2004. // Distributed under the Boost Software License, Version 1.0. // (See accompanying file LICENSE_1_0.txt // or copy at http://www.boost.org/LICENSE_1_0.txt) // This file defines template functions that are declared in // ../value_semantic.hpp. #include <boost/throw_exception.hpp> // forward declaration namespace boost { template<class T> class optional; } namespace boost { namespace program_options { extern BOOST_PROGRAM_OPTIONS_DECL std::string arg; template<class T, class charT> std::string typed_value<T, charT>::name() const { std::string const& var = (m_value_name.empty() ? arg : m_value_name); if (!m_implicit_value.empty() && !m_implicit_value_as_text.empty()) { std::string msg = "[=" + var + "(=" + m_implicit_value_as_text + ")]"; if (!m_default_value.empty() && !m_default_value_as_text.empty()) msg += " (=" + m_default_value_as_text + ")"; return msg; } else if (!m_default_value.empty() && !m_default_value_as_text.empty()) { return var + " (=" + m_default_value_as_text + ")"; } else { return var; } } template<class T, class charT> void typed_value<T, charT>::notify(const boost::any& value_store) const { const T* value = boost::any_cast<T>(&value_store); if (m_store_to) { *m_store_to = *value; } if (m_notifier) { m_notifier(*value); } } namespace validators { /* If v.size() > 1, throw validation_error. If v.size() == 1, return v.front() Otherwise, returns a reference to a statically allocated empty string if 'allow_empty' and throws validation_error otherwise. */ template<class charT> const std::basic_string<charT>& get_single_string( const std::vector<std::basic_string<charT> >& v, bool allow_empty = false) { static std::basic_string<charT> empty; if (v.size() > 1) boost::throw_exception(validation_error(validation_error::multiple_values_not_allowed)); else if (v.size() == 1) return v.front(); else if (!allow_empty) boost::throw_exception(validation_error(validation_error::at_least_one_value_required)); return empty; } /* Throws multiple_occurrences if 'value' is not empty. */ BOOST_PROGRAM_OPTIONS_DECL void check_first_occurrence(const boost::any& value); } using namespace validators; /** Validates 's' and updates 'v'. @pre 'v' is either empty or in the state assigned by the previous invocation of 'validate'. The target type is specified via a parameter which has the type of pointer to the desired type. This is workaround for compilers without partial template ordering, just like the last 'long/int' parameter. */ template<class T, class charT> void validate(boost::any& v, const std::vector< std::basic_string<charT> >& xs, T*, long) { validators::check_first_occurrence(v); std::basic_string<charT> s(validators::get_single_string(xs)); try { v = any(lexical_cast<T>(s)); } catch(const bad_lexical_cast&) { boost::throw_exception(invalid_option_value(s)); } } BOOST_PROGRAM_OPTIONS_DECL void validate(boost::any& v, const std::vector<std::string>& xs, bool*, int); #if !defined(BOOST_NO_STD_WSTRING) BOOST_PROGRAM_OPTIONS_DECL void validate(boost::any& v, const std::vector<std::wstring>& xs, bool*, int); #endif // For some reason, this declaration, which is require by the standard, // cause msvc 7.1 to not generate code to specialization defined in // value_semantic.cpp #if ! ( BOOST_WORKAROUND(BOOST_MSVC, == 1310) ) BOOST_PROGRAM_OPTIONS_DECL void validate(boost::any& v, const std::vector<std::string>& xs, std::string*, int); #if !defined(BOOST_NO_STD_WSTRING) BOOST_PROGRAM_OPTIONS_DECL void validate(boost::any& v, const std::vector<std::wstring>& xs, std::string*, int); #endif #endif /** Validates sequences. Allows multiple values per option occurrence and multiple occurrences. */ template<class T, class charT> void validate(boost::any& v, const std::vector<std::basic_string<charT> >& s, std::vector<T>*, int) { if (v.empty()) { v = boost::any(std::vector<T>()); } std::vector<T>* tv = boost::any_cast< std::vector<T> >(&v); assert(NULL != tv); for (unsigned i = 0; i < s.size(); ++i) { try { /* We call validate so that if user provided a validator for class T, we use it even when parsing vector<T>. */ boost::any a; std::vector<std::basic_string<charT> > cv; cv.push_back(s[i]); validate(a, cv, (T*)0, 0); tv->push_back(boost::any_cast<T>(a)); } catch(const bad_lexical_cast& /*e*/) { boost::throw_exception(invalid_option_value(s[i])); } } } /** Validates optional arguments. */ template<class T, class charT> void validate(boost::any& v, const std::vector<std::basic_string<charT> >& s, boost::optional<T>*, int) { validators::check_first_occurrence(v); validators::get_single_string(s); boost::any a; validate(a, s, (T*)0, 0); v = boost::any(boost::optional<T>(boost::any_cast<T>(a))); } template<class T, class charT> void typed_value<T, charT>:: xparse(boost::any& value_store, const std::vector<std::basic_string<charT> >& new_tokens) const { // If no tokens were given, and the option accepts an implicit // value, then assign the implicit value as the stored value; // otherwise, validate the user-provided token(s). if (new_tokens.empty() && !m_implicit_value.empty()) value_store = m_implicit_value; else validate(value_store, new_tokens, (T*)0, 0); } template<class T> typed_value<T>* value() { // Explicit qualification is vc6 workaround. return boost::program_options::value<T>(0); } template<class T> typed_value<T>* value(T* v) { typed_value<T>* r = new typed_value<T>(v); return r; } template<class T> typed_value<T, wchar_t>* wvalue() { return wvalue<T>(0); } template<class T> typed_value<T, wchar_t>* wvalue(T* v) { typed_value<T, wchar_t>* r = new typed_value<T, wchar_t>(v); return r; } }}