external_libraries/yaml-cpp-0.3.0/src/conversion.cpp

   1 #include "yaml-cpp/conversion.h"
   2 #include <algorithm>
   3
   4 ////////////////////////////////////////////////////////////////
   5 // Specializations for converting a string to specific types
   6
   7 namespace
   8 {
   9         // we're not gonna mess with the mess that is all the isupper/etc. functions
  10         bool IsLower(char ch) { return 'a' <= ch && ch <= 'z'; }
  11         bool IsUpper(char ch) { return 'A' <= ch && ch <= 'Z'; }
  12         char ToLower(char ch) { return IsUpper(ch) ? ch + 'a' - 'A' : ch; }
  13
  14         std::string tolower(const std::string& str)
  15         {
  16                 std::string s(str);
  17                 std::transform(s.begin(), s.end(), s.begin(), ToLower);
  18                 return s;
  19         }
  20
  21         template <typename T>
  22         bool IsEntirely(const std::string& str, T func)
  23         {
  24                 for(std::size_t i=0;i<str.size();i++)
  25                         if(!func(str[i]))
  26                                 return false;
  27
  28                 return true;
  29         }
  30
  31         // IsFlexibleCase
  32         // . Returns true if 'str' is:
  33         //   . UPPERCASE
  34         //   . lowercase
  35         //   . Capitalized
  36         bool IsFlexibleCase(const std::string& str)
  37         {
  38                 if(str.empty())
  39                         return true;
  40
  41                 if(IsEntirely(str, IsLower))
  42                         return true;
  43
  44                 bool firstcaps = IsUpper(str[0]);
  45                 std::string rest = str.substr(1);
  46                 return firstcaps && (IsEntirely(rest, IsLower) || IsEntirely(rest, IsUpper));
  47         }
  48 }
  49
  50 namespace YAML
  51 {
  52         bool Convert(const std::string& input, bool& b)
  53         {
  54                 // we can't use iostream bool extraction operators as they don't
  55                 // recognize all possible values in the table below (taken from
  56                 // http://yaml.org/type/bool.html)
  57                 static const struct {
  58                         std::string truename, falsename;
  59                 } names[] = {
  60                         { "y", "n" },
  61                         { "yes", "no" },
  62                         { "true", "false" },
  63                         { "on", "off" },
  64                 };
  65
  66                 if(!IsFlexibleCase(input))
  67                         return false;
  68
  69                 for(unsigned i=0;i<sizeof(names)/sizeof(names[0]);i++) {
  70                         if(names[i].truename == tolower(input)) {
  71                                 b = true;
  72                                 return true;
  73                         }
  74
  75                         if(names[i].falsename == tolower(input)) {
  76                                 b = false;
  77                                 return true;
  78                         }
  79                 }
  80
  81                 return false;
  82         }
  83
  84         bool Convert(const std::string& input, _Null& /*output*/)
  85         {
  86                 return input.empty() || input == "~" || input == "null" || input == "Null" || input == "NULL";
  87         }
  88 }
  89