![\"RawAndCookedEng\"](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2016\/10\/RawAndCookedEng.png\")
<\/p>\n
How should you read the table? The data type character has the form character_suffix. An example is ‘s’_c.<\/span> The compiler invokes the literal operator operator”” _c(‘s’)<\/span>. The character is, in this case, a char. C++ supports, in addition to the data type The compiler can map integers or floating-point numbers to integers (unsigned long long int<\/span>) or floating-point numbers (long double), but the compiler can also map them to C strings. The first variant is called the cooked form; the second variant is the raw form. The compiler will use the raw form if the literal operator wants its arguments as a C string. If not, it uses the cooked form. If you implement both versions, the compiler will choose the cooked form.<\/p>\n Admittedly, in the last lines is a lot of confusion potential. Therefore, I sum it all up from the perspective of the signatures in the following table. The first column has the signature of the literal operator, the second column is the type of the user-defined literal, and the last column an example for a user-defined literal that fits the signature of the literal operator.<\/p>\n I calculated in the post user-defined literals <\/a>how many meters I have to go by car on average per week. I made my calculation based on user-defined literals of the type long double in the cooked form. I have to adjust the literal operators to make my calculation in the raw form.<\/p>\n It’s only necessary to convert the arguments of the literal operator from type C string to long double<\/span>. That is relatively easy to do with the new function std::stold.<\/span><\/a><\/p>\n <\/p>\n <\/p>\n Either I have not touched the class MyDistance.<\/span><\/p>\n <\/p>\n <\/p>\n <\/p>\n Nor does the main program need a modification.<\/p>\n <\/p>\n <\/p>\nchar<\/code><\/span> the data types wchar_t, char16_t,<\/span> and char32_t<\/span>. You can use this type as a base for your C string. I used in the table a char<\/code>. The table shows that the compiler maps the C string “hi”_i18<\/span> to the literal operator operator”” _i18n(“hi”,2). <\/span><\/span> <\/span> <\/span> <\/span>2 is the length of the c string.<\/span><\/span> <\/span> <\/span> <\/span><\/p>\n![\"literaleSignaturEng\"](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2016\/10\/literaleSignaturEng.png\")
<\/p>\n<\/p>\nCalculate it once more<\/h2>\n
\n\n
\n \n 1\r\n 2\r\n 3\r\n 4\r\n 5\r\n 6\r\n 7\r\n 8\r\n 9\r\n10\r\n11\r\n12\r\n13\r\n14\r\n15\r\n16\r\n17\r\n18\r\n19\r\n20\r\n21\r\n22\r\n23\r\n24\r\n25\r\n26<\/pre>\n<\/td>\n
\n \/\/ unit.h<\/span>\r\n\r\n#ifndef UNIT_H<\/span>\r\n#define UNIT_H<\/span>\r\n\r\n#include <distance.h><\/span>\r\n\r\nnamespace<\/span> Distance{\r\n\r\n namespace<\/span> Unit{\r\n MyDistance operator<\/span> \"\"<\/span> _km(const<\/span> char<\/span>* k){\r\n return<\/span> MyDistance(1000* std::stold(k));\r\n }\r\n MyDistance operator<\/span> \"\"<\/span> _m(const<\/span> char<\/span>* m){\r\n return<\/span> MyDistance(std::stold(m));\r\n }\r\n MyDistance operator<\/span> \"\"<\/span> _dm(const<\/span> char<\/span>* d){\r\n return<\/span> MyDistance(std::stold(d)\/10);\r\n }\r\n MyDistance operator<\/span> \"\"<\/span> _cm(const<\/span> char<\/span>* c){\r\n return<\/span> MyDistance(std::stold(c)\/100);\r\n }\r\n }\r\n}\r\n\r\n#endif<\/span>\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n\n
\n \n 1\r\n 2\r\n 3\r\n 4\r\n 5\r\n 6\r\n 7\r\n 8\r\n 9\r\n10\r\n11\r\n12\r\n13\r\n14\r\n15\r\n16\r\n17\r\n18\r\n19\r\n20\r\n21\r\n22\r\n23\r\n24\r\n25\r\n26\r\n27\r\n28\r\n29\r\n30\r\n31\r\n32\r\n33\r\n34\r\n35\r\n36\r\n37\r\n38\r\n39\r\n40\r\n41\r\n42\r\n43\r\n44\r\n45\r\n46\r\n47\r\n48<\/pre>\n<\/td>\n
\n \/\/ distance.h<\/span>\r\n\r\n#ifndef DISTANCE_H<\/span>\r\n#define DISTANCE_H<\/span>\r\n\r\n#include <iostream><\/span>\r\n#include <ostream><\/span>\r\n\r\n\r\nnamespace<\/span> Distance{\r\n class<\/span> MyDistance<\/span>{\r\n public:\r\n MyDistance(double<\/span> i):m(i){}\r\n\r\n friend<\/span> MyDistance operator<\/span>+(const<\/span> MyDistance& a, const<\/span> MyDistance& b){\r\n return<\/span> MyDistance(a.m + b.m);\r\n }\r\n friend<\/span> MyDistance operator<\/span>-(const<\/span> MyDistance& a,const<\/span> MyDistance& b){\r\n return<\/span> MyDistance(a.m - b.m);\r\n }\r\n\t \r\n\t friend<\/span> MyDistance operator<\/span>*(double<\/span> m, const<\/span> MyDistance& a){\r\n\t return<\/span> MyDistance(m*a.m);\r\n\t }\r\n\t \r\n\t friend<\/span> MyDistance operator<\/span>\/(const<\/span> MyDistance& a, int<\/span> n){\r\n\t return<\/span> MyDistance(a.m\/n);\r\n\t }\r\n\t \r\n friend<\/span> std::ostream& operator<\/span><< (std::ostream &out, const<\/span> MyDistance& myDist){\r\n out << myDist.m << \" m\"<\/span>;\r\n return<\/span> out;\r\n }\r\n\tprivate:\r\n\t double<\/span> m;\r\n\t \r\n };\r\n \r\n}\r\n \r\nDistance::MyDistance getAverageDistance(std::initializer_list<Distance::MyDistance> inList){\r\n auto<\/span> sum= Distance::MyDistance{0.0};\r\n for<\/span> (auto<\/span> i: inList) sum = sum + i ;\r\n return<\/span> sum\/inList.size(); \r\n}\r\n\r\n\r\n#endif<\/span>\r\n<\/pre>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n
![\"average\"](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2016\/10\/average.png\")
<\/p>\n![\"CppLiteralsEng\"](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2016\/10\/CppLiteralsEng.png\")
<\/p>\n![\"schoolDay\"](\"https:\/\/www.modernescpp.com\/wp-content\/uploads\/2016\/10\/schoolDay.PNG\")
<\/p>\n