std::string\u6587\u5b57\u5217\u304cfloat\u306b\u306a\u308a\u5f97\u308b\u304b\u3069\u3046\u304b\u3092\u30c1\u30a7\u30c3\u30af\u3057\u3064\u3064float\u3078\u306e\u5909\u63db\u3092\u884c\u3046\u5834\u5408\u3001\u901a\u5e38\u306fstd::stof\u3092\u7528\u3044\u3066<\/p>\n
\/\/ Copyright SCIEMENT, Inc.\r\n\/\/ by Hirofumi Seo, M.D., CEO & President\r\n\r\n#include <string>\r\n#include <iostream>\r\n\r\nfloat stofTryCacth(const std::string& a, bool* is_float) {\r\n float result = 0.0f;\r\n try {\r\n result = std::stof(a);\r\n }\r\n catch (const std::invalid_argument&) {\r\n std::cout << \"Error: The string '\" << a << \"' is not float.\" << std::endl;\r\n *is_float = false;\r\n return result;\r\n }\r\n catch (const std::out_of_range&) {\r\n std::cout << \"Error: The string '\" << a << \"' is float but out of range.\" << std::endl;\r\n *is_float = false;\r\n return result;\r\n }\r\n *is_float = true;\r\n std::cout << \"'\" << a << \"' -> \" << result << std::endl;\r\n return result;\r\n}\r\n \r\nint main() {\r\n float result;\r\n bool is_float;\r\n\r\n result = stofTryCacth(\"3.14\", &is_float); \/\/ '3.14' -> 3.14\r\n result = stofTryCacth(\" 3.14\", &is_float); \/\/ ' 3.14' -> 3.14\r\n result = stofTryCacth(\"3.14 \", &is_float); \/\/ '3.14 ' -> 3.14\r\n result = stofTryCacth(\" 3.14 \", &is_float); \/\/ ' 3.14 ' -> 3.14\r\n result = stofTryCacth(\"3.14abc\", &is_float); \/\/ '3.14abc' -> 3.14\r\n result = stofTryCacth(\"abc3.14\", &is_float); \/\/ Error: The string 'abc3.14' is not float.\r\n result = stofTryCacth(\"abc\", &is_float); \/\/ Error: The string 'abc' is not float.\r\n result = stofTryCacth(\"3.14e2\", &is_float); \/\/ '3.14e2' -> 314\r\n result = stofTryCacth(\"3.14e-2\", &is_float); \/\/ '3.14e-2' -> 0.0314\r\n result = stofTryCacth(\"314.e-2\", &is_float); \/\/ '314.e-2' -> 3.14\r\n result = stofTryCacth(\".314e-2\", &is_float); \/\/ '.314e-2' -> 0.00314\r\n result = stofTryCacth(\"3.14e100\", &is_float); \/\/ Error: The string '3.14e100' is float but out of range.\r\n result = stofTryCacth(\"-3.14e100\", &is_float); \/\/ Error: The string '-3.14e100' is float but out of range.\r\n\r\n return 0;\r\n}<\/pre>\n\u306e\u3088\u3046\u306b\u884c\u3046\u304b\u3068\u601d\u3044\u307e\u3059\u3002\u305f\u3060\u3001\u3053\u306e\u307e\u307e\u3067\u3059\u306835\u884c\u76ee\u306b\u3042\u308b\u3088\u3046\u306b\u5c0f\u6570\u306e\u5f8c\u306b\u4f59\u8a08\u306a\u6587\u5b57\u5217\u304c\u9023\u7d9a\u3057\u3066\u3044\u308b\u3088\u3046\u306a\u5834\u5408\u3067\u3082\u5c0f\u6570\u3068\u3057\u3066\u751f\u6210\u3055\u308c\u3066\u3057\u307e\u3044\u307e\u3059<\/strong>\u306e\u3067\u3001
\n\u53b3\u5bc6\u306b\u306fstd::stof\u306e\u7b2c\u4e8c\u5f15\u6570 size_t* _Idx\u3092\u7528\u3044\u3066\u30b4\u30cb\u30e7\u30b4\u30cb\u30e7\u3059\u308b\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\u7d0410\u4e07\u500b\u306efloat\u6587\u5b57\u5217\u3092float\u578b\u306b\u5909\u63db\u3059\u308b\u306e\u306b560 msec\u7a0b\u5ea6\u3067\u7d42\u308f\u308a\u307e\u3057\u305f\u3002\u7d040.5\u79d2\u3061\u3087\u3063\u3068<\/font>\u3067\u3059\u3002<\/strong><\/p>\n\u3061\u306a\u307f\u306btry \/ catch\u3092\u4f7f\u308f\u305a\u306b\u5358\u306bstd::stof\u3092\u7528\u3044\u3066\u3057\u307e\u3046\u3068<\/p>\n
\/\/ Copyright SCIEMENT, Inc.\r\n\/\/ by Hirofumi Seo, M.D., CEO & President\r\n\r\n#include <string>\r\n#include <iostream>\r\n\r\nint main() {\r\n const float result = std::stof(\"abc\"); \/\/ \u3053\u3053\u3067\u30d5\u30ea\u30fc\u30ba\u3057\u3066\u3057\u307e\u3046\u3002\r\n std::cout << \"abc\" << result << std::endl;\r\n return 0;\r\n}<\/pre>\n\u4e0a\u8a18\u306e\u3088\u3046\u306b\u3001float\u306b\u5909\u63db\u51fa\u6765\u306a\u3044\u5024\u3092\u4e0e\u3048\u308b\u3068\u30d5\u30ea\u30fc\u30ba\u3057\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/p>\n
\u3067\u3001\u6b8b\u5ff5\u306a\u3053\u3068\u306bUnreal Engine\u3067\u306ftry \/ catch\u306e\u4f7f\u7528\u306f\u63a8\u5968\u3055\u308c\u3066\u304a\u3089\u305a\u3001\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u306f\u7121\u52b9\u306b\u306a\u3063\u3066\u3044\u307e\u3059<\/strong>\u3002
\n\u4e00\u5fdc\u3001\u56de\u907f\u65b9\u6cd5\u306f\u3042\u308b\u306e\u3067\u3059\u304c\u3001<\/p>\n\u53c2\u8003\u8a18\u4e8b\uff1a
\nHow can I enable unwind semantics for C++-style exceptions? - UE4 AnswerHub<\/a><\/strong><\/p>\n\u30d0\u30fc\u30b8\u30e7\u30f3\u3054\u3068\u306b\u6307\u5b9a\u65b9\u6cd5\u304c\u7570\u306a\u308b\u306a\u3069\u3001\u3084\u306f\u308a\u7121\u7406\u3084\u308a\u306a\u65b9\u6cd5\u3067\u3042\u308b\u611f\u306f\u5426\u3081\u307e\u305b\u3093\u3002<\/p>\n
\u3068\u306a\u308b\u3068try \/ catch\u3092\u4f7f\u308f\u305a\u306bstd::string -> float\u3078\u306e\u5909\u63db\u3092\u5b89\u5168\u306b\u884c\u3044\u305f\u3044\u308f\u3051\u3067\u3059\u3002<\/p>\n
\u307e\u305a\u601d\u3044\u3064\u304f\u65b9\u6cd5\u306f\u3001\u6b63\u898f\u8868\u73fe\u3092\u99c6\u4f7f\u3059\u308b\u65b9\u6cd5\u3067\u3059\u3002\u3053\u3053\u306f\u7d20\u76f4\u306b\u5049\u5927\u306a\u308b\u5148\u4eba\u305f\u3061\u306e\u77e5\u6075\u3092\u4f7f\u3044\u307e\u3057\u3087\u3046\u3002<\/p>\n
\u53c2\u8003\u8a18\u4e8b\uff1a
\nExample: Matching Floating Point Numbers with a Regular Expression<\/strong><\/a><\/p>\n\/\/ Copyright SCIEMENT, Inc.\r\n\/\/ by Hirofumi Seo, M.D., CEO & President\r\n\r\n#include <string>\r\n#include <regex>\r\n\r\nbool CheckIsFloat(const std::string& x) {\r\n std::regex e1(\"[-+]?[0-9]*[.]?[0-9]+([eE][-+]?[0-9]+)?\");\r\n std::regex e2(\"[-+]?[0-9]+[.]\");\r\n return std::regex_match(x, e1) || std::regex_match(x, e2);\r\n}<\/pre>\n\u307f\u305f\u3044\u306a\u95a2\u6570\u3092\u4f5c\u3063\u3066\u3084\u3063\u3066\u78ba\u8a8d\u3059\u308c\u3070OK\u3067\u3059\u3002\u305f\u3060\u3001\u5c11\u306a\u304f\u3068\u3082\u79c1\u306e\u74b0\u5883\u3067\u306f\u3001\u3053\u306e\u65b9\u6cd5\u306f\u901f\u5ea6\u304c\u975e\u5e38\u306b\u9045\u304f\u306a\u3063\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002
\n\u4e0a\u8a18\u3068\u540c\u3058\u7d0410\u4e07\u500b\u306efloat\u6587\u5b57\u5217\u3092float\u578b\u306b\u5909\u63db\u3059\u308b\u306e\u306b4268 msec\u3082\u8981\u3057\u3066\u3057\u307e\u3044\u307e\u3057\u305f\u3002\u7d044\u79d2<\/font>\u3067\u3059\u3002<\/strong>
\n\u3057\u304b\u3082\u3001\u6b63\u78ba\u306b\u306ffloat\u306e\u7bc4\u56f2\u5185\u306b\u5c0f\u6570\u306e\u5024\u304c\u53ce\u307e\u3063\u3066\u3044\u308b\u304b\u3069\u3046\u304b\u306a\u3069\u306e\u30c1\u30a7\u30c3\u30af\u3082\u3053\u306e\u5f8c\u8ffd\u52a0\u3067\u884c\u3046\u5fc5\u8981\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n\/\/------2018\/5\/15\u52a0\u7b46------<\/strong>
\n\u4e0a\u8a18\u6b63\u898f\u8868\u73fe\u3092\u7528\u3044\u305f\u65b9\u6cd5\u306b\u95a2\u3057\u3066\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30b3\u30e1\u30f3\u30c8\u3092\u9802\u304d\u307e\u3057\u305f\u3002<\/p>\n\n\u8a18\u4e8b\u306e\u672c\u8cea\u3068\u306f\u5c11\u3057\u305a\u308c\u307e\u3059\u304c\u3001std::regex\u304c\u3053\u306e\u4f7f\u3044\u65b9\u3067\u6975\u3081\u3066\u9045\u3044\u306e\u306fstd::regex\u3092\u95a2\u6570\u547c\u3073\u51fa\u3057\u306e\u5ea6\u306b\u751f\u6210\u3057\u3066\u3044\u308b\u5f71\u97ff\u304c\u652f\u914d\u7684\u3060\u3068\u601d\u3046\u306e\u3067\u3001 regex \u3092 static \u3067\u5b9a\u7fa9\u3059\u308b\u3060\u3051\u3067\u305d\u3053\u306f4\u6841\u304f\u3089\u3044\u901f\u304f\u306a\u308b\u3068\u601d\u3046\u3002\u3044\u307e wandbox \u304c 405 \u5410\u304f\u3088\u3046\u306a\u306e\u3067\u5b9f\u9a13\u306f\u7701\u7565\u3059\u308b\u3051\u3069\u30fb\uff57\u30fb https:\/\/t.co\/ugjOTdcF0y<\/a><\/p>\n— \u30c7\u30b9\u5473\uff08\u30c7\u30b9\u30fb\u30a6\u30a7\u30a4\uff09\u3046\u3055\u304e \/\/ Usagi Ito (@USAGI_WRP) 2018\u5e745\u670815\u65e5<\/a><\/p><\/blockquote>\n