How to include character literals?

Question

I have a question on how to include string literals when getting info from a file. Let me show my code for better understanding:

Program.b:

print \"Hello World\n\"; print \"Commo Estas :)\n\"; print \"Bonjour\";print \"Something\"; return 0;

main.cpp (I have minimized the actual file to what is needed for this question):

int main()
{
    std::string file_contents;
    std::fstream file;
    file.open("Program.b");
    std::ifstream file_read;
    file_read.open("Program.b");

    if(file_read.is_open())
        while(getline(file_read,file_contents));

    cout << file_contents << endl;

}

So right now when I print file_contents, I get:

print \"Hello World\n\"; print \"Commo Estas :)\n\"; print \"Bonjour\";print \"Something\"; return 0;

You can see it includes the \n . Is there a way to make that an actual character literal, so printing it actually prints a new line? (I would want the same for quotation marks.)

Answer 1

Try something like this:

Program.b

R"inp(print "Hello World\n"; print "Commo Estas :)\n"; print "Bonjour";print "Something"; return 0;)inp"

---

main.cpp

int main() {
    std::string file contents = 
    #include "Program.b"
    ;
    std::cout << file_contents << std::endl;

}

---

You can also change Program.b to make it a bit more readable:

R"inp(
print "Hello World\n"; 
print "Commo Estas :)\n"; 
print "Bonjour";
print "Something"; 
return 0;
)inp"

---

The runtime variant should be simply:

Program.b

print "Hello World\n"; 
print "Commo Estas :)\n"; 
print "Bonjour";
print "Something"; 
return 0;

main.cpp

int main()
{
    std::string file_contents;
    std::fstream file;
    file.open("Program.b");
    std::ifstream file_read;
    file_read.open("Program.b");

    if(file_read.is_open()) {
        std::string line;
        while(getline(file_read,line)) {
             file_contents += line + `\n`;
        }
    }

    cout << file_contents << endl;

}

Answer 2

You can do a simple find + replace.

std::size_t pos = std::string::npos;
while ((pos = file_contents.find("\\n")) != std::string::npos)
    file_contents.replace(pos, 1, "\n");

//Every \n will have been replaced by actual newline character