Question

My code, when compiled, returns the error invalid conversion from ‘char*’ to ‘char’, and identifies the second last line, return char32 as the problem. I’ve searched the Internet and this site and haven’t found anything that has helped. I’ve found the error goes away and the code compiles if I replace the problem line with return *char32, but I’m not entirely sure why this should be the case. I understand that this is pointer notation, but I’m unsure how they apply to this situation. Also, when I do this and attempt to print *char32 to the terminal, nothing happens, indicating that *char32 in empty. I’ve also verified that there is indeed a line being read in from the file some file.

Update 1: I am attempting to return a full array from parse().

Update 2: I realise I didn’t state my goal for this code. I am attempting to read the first line from the some file, pass it to parse() and have the first 32 characters indexed into the array char32, which will then be passed back to main(). Sorry for the confusion.

#include <fstream>
#include <iostream>
#include <string>
using namespace std;

char parse(string line), char32[32];

int main()
{
    string line;
    ifstream vgv;
    vgv.open("some file");

    getline(vgv, line);
    cout << char32;

    return 0;
}

char parse(string line)
{
    int size = line.size();
    for (int count1 = 0; count1 < 32; count1 ++)
    {
        char32[count1] = line[count1];
    }

    return char32;
}   

Answer 1

There are many problems here.

If you really want to return a single character that should be

return char32[0];

or whichever character you want, by index. This is the same as *char32 by the way. An array variable can be treated as a pointer to the first array in the element, if no index is used. Although since char32 is a global it’s not really adding any value above the function returning void – the caller can just access char32 directly. If you want to output the results using cout it would be better to return a new string from parse.

You should stop the loop in parse when you reach min(size, 32), or you will overrun the input string in line with undefined results (bad, typically). it would be a good idea to allow space for a null terminator here – again using string would just obviate this.

Magic numbers are evil. Use this instead of the hard-coded 32:

const size_t MAX_LENGTH(32);

If all parse does is byte-by-byte copy, you could use std::copy but I suspect this is a prototype for a real parser you plan to build once interface issues are resolved. I think you are missing a call to char myresult = parse(line); before you output char32 to cout by the way.