Member Avatar for rapt0r

In a c++ tutorial this was one way to define a string

#include <string>
using namespace std;

string name;
name="mark";

But it dosent work i get errors.Why is this?

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  • Latest Post Latest Post by ~s.o.s~

Dani AI

Generated

The original compile failures come from two separate things: trying to use an assignment statement at namespace (global) scope, and a few small syntax typos in the class code. correctly asked about a main() function, was right to stress the difference between initialization and assignment, and spotted the missing parentheses on the destructor. Below is a short clarification and a safe, idiomatic pattern.

At namespace scope a definition may perform initialization, but standalone assignment statements are not allowed. For example, this is valid at global scope:

std::string globalName = "mark";   // initialization at declaration — OK

This is not valid outside any function:

globalName = "mark";               // illegal at namespace scope — must be inside a function

For class members prefer a constructor initializer list and make sure function signatures are correct (no stray semicolon after int main(), destructor must be ~Name() including ()):

#include <iostream>
#include <string>

class Name {
    std::string myname;
public:
    Name();
    ~Name();
    void print() const;
};

Name::Name() : myname("mark") { }
Name::~Name() { }
void Name::print() const { std::cout << myname << '\n'; }

std::string globalName = "mark";

int main() {
    std::cout << "global: " << globalName << '\n';
    Name firstname;
    firstname.print();
    return 0;
}

Quick troubleshooting notes: common compiler diagnostics will point to the first syntax problem — a stray semicolon after int main() or a missing () on ~Name typically produces confusing follow-up errors. Using -Wall -Wextra (or enabling warnings in the IDE) makes these issues obvious. Also prefer explicit std:: qualifiers in small examples to avoid ambiguity while learning.

Recommended Answers

All 7 Replies

Member Avatar for Eddy Dean

Don't you think you need a Main() function?

Member Avatar for rapt0r

Don't you think you need a Main() function?

yes a got a main function

#include <iostream>
#include <string>
string name;
name="mark";

int main()
{
     cout<<name;
     return 0;
}
Member Avatar for Eddy Dean 
#include <iostream>
#include <string>


int main()
{
string name;
name="mark";
     cout<<name;
     return 0;
}
Member Avatar for Lerner

or maybe:

#include <iostream>
#include <string>
string name("mark");  //this is initialization, not assignment


int main()
{
     cout<<name;
     return 0;
}

However, I don't think you can assign values to global variables outside of a function.

Member Avatar for rapt0r

Thx that worked but now i want to put a string in a class i tryed this

#include <iostream>
#include <string>

class Name
{
     string myname;
public:
     Name();
     ~Name();
     void print();
};
Name::Name()
{
     myname="mark";
}
Name::~Name
{
}
void Name::print()
{
     cout<<myname;
     
}
int main();
{
     Name firstname;
     firstname.print();
     return 0;
}

Didnt work

Member Avatar for rapt0r

never mind got it working:)

Member Avatar for ~s.o.s~

Thx that worked but now i want to put a string in a class i tryed this Didnt work

I have highlighted the section which you forgot towrite or had wrongly written.

Try this

#include <iostream>
#include <string>

class Name
{
     string myname;
public:
     Name();
     ~Name();
     void print();
};

Name::Name()
{
     myname="mark";
}
Name::~Name ()
{
}
void Name::print()
{
     cout<<myname;
     
}
int main();
{
     Name firstname;
     firstname.print();
     return 0;
}

It would be really better if you started C++ using some basic c++ tutorials, get the basics straight, read some theory and then start programming.

Hope it helped,
bye.

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