Question

//Prints out a given array 
template <typename T>
void print(T t)
{
    for(int i = 0; i < t.size(); i++)
    {
        cout << t[i] << " ";
    }
    cout << endl;
}

I have an idea but it includes passing the size of the array. Is it possible to avoid this?

*Update
Thanks for all of the answers/ideas but this problem is getting way deeper than my snorkeler can handle. I wanted to rewrite my C++ code in C because it was horribly written and slow. I see now that I have an opportunity to make it even worse in C. I’ll rewrite it from the ground up in Python(performance be damned). Thanks again

Answer 1

If you don’t have ELEMENTS, it’s

#define ELEMENTS(a) (sizeof(a)/sizeof(*a))

Then,

#define print_array(a, specifier) print_array_impl(a, specifier, ELEMENTS(a), sizeof(*a))

void print_array_impl(void* a, char* specifier, size_t asize, size_t elsize)
{
    for(int i = 0; i < asize; i++)
    {
        // corrected based on comment -- unfortunately, not as general
        if (strcmp(specifier, "%d") == 0)
           printf(specifier, ((int*)a)[i]); 
        // else if ... // check other specifiers
        printf(" ");
    }
    printf("\n");
}

Use like this

print_array(a, "%d") // if a is a int[]

and, a needs to be an array name, not a pointer (or else ELEMENTS won’t work)