小编Bry*_*yce的帖子

std::unordered_map<std::string, std::string> mimeMap = {
    #define STR_PAIR(K,V) std::pair<std::string, std::string>(K,V)
    #include "MimeTypes.inc"
};

文件MimeTypes.inc如:

STR_PAIR("3dm", "x-world/x-3dmf"),
STR_PAIR("3dmf", "x-world/x-3dmf"),
STR_PAIR("a", "application/octet-stream"),
STR_PAIR("aab", "application/x-authorware-bin"),
STR_PAIR("aam", "application/x-authorware-map"),
STR_PAIR("aas", "application/x-authorware-seg"),
STR_PAIR("abc", "text/vnd.abc"),
STR_PAIR("acgi", "text/html"),
STR_PAIR("afl", "video/animaflex"),
STR_PAIR("ai", "application/postscript"),
STR_PAIR("aif", "audio/aiff"),

我很迷茫.这段代码如何初始化unordered_map？