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#include <iostream>
#include <functional>
#include "generator.h"
void* operator new([[maybe_unused]]std::size_t n)
{
std::cout << "new\n";
throw std::bad_alloc();
}
void operator delete(void*) throw()
{
std::cout << "delete\n";
// Do nothing. actual memory is allocated on the stack
}
void operator delete(void*, std::size_t) throw()
{
std::cout << "delete[]\n";
// Do nothing. actual memory is allocated on the stack
}
template<typename T>
Generator<T> iota(T start)
{
while(true)
{
co_yield start++;
}
}
int main()
{
std::cout << " ** std::string:\n";
{
std::string str(15, 'a'); // 15 characters + zero termination - ok
str = "123456789012345"; // 15 characters + zero termination - ok
try
{
str = "1234567890123456"; // 16 characters + zero termination
}
catch(std::bad_alloc &e)
{
std::cout << "Too big for SSO!\n";
}
}
std::cout << '\n';
std::cout << " ** std::vector:\n";
{
try
{
std::vector<int> vec{42}; // even one element is too much, no SBO
}
catch(std::bad_alloc &e)
{
std::cout << "No SBO for std::vector!\n";
}
}
std::cout << '\n';
std::cout << " ** std::function:\n";
{
{
std::function<int()> f;
char foo[16]{};
f = [foo]() // capture up to 16 bytes is ok for std::function
{
int i = 0;
for(auto v : foo) i += v;
return i;
};
}
// try // this line seem to break gcc...
// {
// std::function<int()> f;
// char foo[17]{};
// f = [foo]()
// {
// int i = 0;
// for(auto v : foo) i += v;
// return i;
// };
// }
// catch(std::bad_alloc &e)
// {
// std::cout << "Too big for SBO in std::function!\n";
// }
}
std::cout << '\n';
std::cout << " ** co-routines:\n";
{
try
{
auto gen = iota(0);
while(true)
{
auto i = gen();
if(i > 10) break;
std::cout << i << " ";
}
std::cout << '\n';
}
catch(std::bad_alloc &e)
{
std::cout << "Co-routines always allocate!\n";
}
}
std::cout << '\n';
}
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