git.sesse.net Git - casparcg/blob - common/param.h

   1 #pragma once
   2
   3 #include "except.h"
   4
   5 #include <boost/lexical_cast.hpp>
   6 #include <boost/algorithm/string.hpp>
   7
   8 #include <type_traits>
   9 #include <string>
  10
  11 namespace caspar {
  12
  13 class param_comparer {
  14                 const std::wstring& lhs;
  15         public:
  16                 explicit param_comparer(const std::wstring& p) : lhs(p) {}
  17                 bool operator()(const std::wstring& rhs) { return boost::iequals(lhs, rhs); }
  18         };
  19
  20 template<typename C>
  21 bool contains_param(const std::wstring& name, C&& params)
  22 {
  23         return std::find_if(params.begin(), params.end(), param_comparer(name)) != params.end();
  24 }
  25
  26 template<typename T, typename C>
  27 typename std::enable_if<!std::is_convertible<T, std::wstring>::value, typename std::decay<T>::type>::type get_param(const std::wstring& name, C&& params, T fail_value = T())
  28 {
  29         auto it = std::find_if(std::begin(params), std::end(params), param_comparer(name));
  30         if(it == params.end())
  31                 return fail_value;
  32
  33         try
  34         {
  35                 if(++it == params.end())
  36                         throw std::out_of_range("");
  37
  38                 return boost::lexical_cast<std::decay<T>::type>(*it);
  39         }
  40         catch(...)
  41         {
  42                 CASPAR_THROW_EXCEPTION(invalid_argument() << msg_info("Failed to parse param.") << arg_name_info(name) << nested_exception(std::current_exception()));
  43         }
  44 }
  45
  46 template<typename C>
  47 std::wstring get_param(const std::wstring& name, C&& params, const std::wstring& fail_value = L"")
  48 {
  49         auto it = std::find_if(std::begin(params), std::end(params), param_comparer(name));
  50         if(it == params.end())
  51                 return fail_value;
  52
  53         try
  54         {
  55                 if(++it == params.end())
  56                         throw std::out_of_range("");
  57
  58                 return *it;
  59         }
  60         catch(...)
  61         {
  62                 CASPAR_THROW_EXCEPTION(invalid_argument() << msg_info("Failed to parse param.") << arg_name_info(name) << nested_exception(std::current_exception()));
  63         }
  64 }
  65
  66 }