iequal.hpp

   1 #ifndef IEQUAL_DOT_HPP
   2 #define IEQUAL_DOT_HPP
   3
   4 #include <algorithm>
   5 #include <cctype>
   6 #include <string_view>
   7
   8 // Like boost, but ASCII only.  Only C locale required.
   9
  10 inline bool iequal_char(char a, char b)
  11 {
  12   return std::toupper(static_cast<unsigned char>(a)) ==
  13          std::toupper(static_cast<unsigned char>(b));
  14 }
  15
  16 inline bool iequal(std::string_view a, std::string_view b)
  17 {
  18   return (size(a) == size(b)) &&
  19          std::equal(begin(b), end(b), begin(a), iequal_char);
  20 }
  21
  22 inline bool iless_char(char a, char b)
  23 {
  24   return std::toupper(static_cast<unsigned char>(a)) <
  25          std::toupper(static_cast<unsigned char>(b));
  26 }
  27
  28 inline bool iless(std::string_view a, std::string_view b)
  29 {
  30   return std::lexicographical_compare(begin(a), end(a), begin(b), end(b),
  31                                       iless_char);
  32 }
  33
  34 inline bool istarts_with(std::string_view str, std::string_view prefix)
  35 {
  36   return (str.size() >= prefix.size()) &&
  37          iequal(str.substr(0, prefix.size()), prefix);
  38 }
  39
  40 struct ci_less {
  41   bool operator()(std::string_view a, std::string_view b) const
  42   {
  43     return iless(a, b);
  44   }
  45 };
  46
  47 // Ahh, the olden days of loops and pointers...
  48
  49 // inline bool iequal(char const* a, char const* b)
  50 // {
  51 //   if (a == b)
  52 //     return true;
  53 //   for (;;) {
  54 //     if (!iequal_char(*a, *b))
  55 //       return false;
  56 //     if (*a == '\0')
  57 //       return true;
  58 //     ++a;
  59 //     ++b;
  60 //   }
  61 // }
  62
  63 #endif // IEQUAL_DOT_HPP