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149 lines (122 loc) · 2.88 KB
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// Copyright (c) 2015
// Author: Chrono Law
#include <std.hpp>
using namespace std;
#include <boost/lexical_cast.hpp>
using namespace boost;
//////////////////////////////////////////
void case1()
{
int x = lexical_cast<int>("100");
long y = lexical_cast<long>("2000");
float pai = lexical_cast<float>("3.14159e5");
double e = lexical_cast<double>("2.71828");
double r = lexical_cast<double>("1.414,xyz", 5);
cout << x << y << pai << e << r << endl;
string str = lexical_cast<string>(456);
cout << str << endl;
cout << lexical_cast<string>(0.618) << endl;
cout << lexical_cast<string>(0x10) << endl;
cout << lexical_cast<bool>("1") << endl;
//lexical_cast<int>("0x100");
//lexical_cast<int>("123L");
}
//////////////////////////////////////////
template<typename T>
bool num_valid(const char *str)
{
T tmp;
return conversion::try_lexical_convert(str, tmp);
}
//try
//{
// lexical_cast<T>(str);
// return true;
//}
//catch(bad_lexical_cast&)
//{
// return false;
//};
void case2()
try
{
assert( num_valid<double>("3.14"));
assert(!num_valid<int>("3.14"));
assert( num_valid<int>("65535"));
int x;
assert(!conversion::try_lexical_convert("0x100", x));
cout << lexical_cast<int>("0x100");
cout << lexical_cast<double>("HelloWorld");
cout << lexical_cast<long>("1000L");
cout << lexical_cast<bool>("false") << endl;
}
catch (bad_lexical_cast& e)
{
cout << "error:" << e.what() << endl;
}
//////////////////////////////////////////
template<typename T>
struct outable
{
friend std::ostream& operator<<(std::ostream& os, const T& x)
{
os << typeid(T).name();
return os;
}
};
class demo_class : public outable<demo_class>
{
// friend std::ostream& operator<<(std::ostream& os, const demo_class& x)
// {
// os << "demo_class's Name";
// return os;
// }
};
void case3()
{
cout << lexical_cast<string>(demo_class()) << endl;
}
//////////////////////////////////////////
void case4()
try
{
assert(stoi(" 42 ") == 42);
assert(stol("100L") == 100L);
assert(stol("1000 9") == 1000L);
assert(stod("3.14ispai") == 3.14);
assert(to_string(776ul) == "776");
//cout << stoul("100L");
//cout << stoul("x100");
cout << stoi("9999999999");
}
catch(std::exception& e)
{
cout << "error:" << e.what() << endl;
}
//////////////////////////////////////////
template<typename T>
T std_lexical_cast(const std::string& s);
template<>
int std_lexical_cast<int>(const std::string& s)
{
return stoi(s);
}
template<>
long std_lexical_cast<long>(const std::string& s)
{
return stol(s);
}
void case5()
{
assert(std_lexical_cast<int>(" 10 ") == 10);
assert(std_lexical_cast<long>("100L") == 100L);
}
//////////////////////////////////////////
int main()
{
case1();
case2();
case3();
case4();
case5();
}