C++模板函数无法在返回时将“std:string”转换为“double”

#include <iostream>
#include <string>
#include <stdexcept>

template <typename T>
T convertString(const std::string& str) {
    if constexpr (std::is_same_v<T, double>) {
        try {
            return std::stod(str);
        } catch (const std::invalid_argument& e) {
            std::cerr << "Invalid argument: " << e.what() << std::endl;
            throw;
        } catch (const std::out_of_range& e) {
            std::cerr << "Out of range: " << e.what() << std::endl;
            throw;
        }
    } else {
        // 处理其他类型的转换
        static_assert(std::is_same_v<T, void>, "Unsupported type");
    }
}

int main() {
    std::string str = "3.14";
    try {
        double result = convertString<double>(str);
        std::cout << "Converted value: " << result << std::endl;
    } catch (const std::exception& e) {
        std::cerr << "Exception: " << e.what() << std::endl;
    }
    return 0;
}