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#include <iostream>
// a basic new feature of C++ are references, they are like
// pointers, but they *can't* be null, which btw in c++ is `nullptr'
// here is a typical C example to use pointers
void inc_ptr_val(int *v) {
// check that v is not null
if (v == nullptr) {
return;
}
// increment where v points
(*v)++;
}
// and here is a new (better) version
void inc_ref_val(int& v) {
// no need to check
// no need to dereference
v++;
}
// an interesting twist is that we can now have const references
// which is like a C "T const * const" ie read only reference
// and is used to not copy big things on the stack
bool is_hello(const std::string& s) {
// s cannot be changed, only read
return s == "hello";
}
int main(int argc, char *arg[]) {
int hello = 10;
std::cout << hello << std::endl;
inc_ptr_val(&hello);
std::cout << hello << std::endl;
inc_ref_val(hello);
std::cout << hello << std::endl;
}
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