why ( const char *ptr = string literal ) works but ( const string *ptr = string literal ) doesn't ?
-
#include
#include
using namespace std;int main(){
const char *ptr = "tarun" ;
//const string *name = "tarun";cout << name << endl ; return 0;}
in the above code if i assign a string literal to a const char*
Quote:
const string *name = "tarun";
it prints the string but the same with string gives error that
Quote:
cannot convert ‘const char’ to ‘const string
so it means any string literal is a const char (which i think is a rvalue), but it is a collection of characters, so how is it a char ? and if it is a char then why it is called string literal ? please explain. Thank you.
-
#include
#include
using namespace std;int main(){
const char *ptr = "tarun" ;
//const string *name = "tarun";cout << name << endl ; return 0;}
in the above code if i assign a string literal to a const char*
Quote:
const string *name = "tarun";
it prints the string but the same with string gives error that
Quote:
cannot convert ‘const char’ to ‘const string
so it means any string literal is a const char (which i think is a rvalue), but it is a collection of characters, so how is it a char ? and if it is a char then why it is called string literal ? please explain. Thank you.
Tarun Jha wrote:
n the above code if i assign a string literal to a const char*
Quote:
const string *name = "tarun";
You may want to change it to
const string name = "tarun";
-
#include
#include
using namespace std;int main(){
const char *ptr = "tarun" ;
//const string *name = "tarun";cout << name << endl ; return 0;}
in the above code if i assign a string literal to a const char*
Quote:
const string *name = "tarun";
it prints the string but the same with string gives error that
Quote:
cannot convert ‘const char’ to ‘const string
so it means any string literal is a const char (which i think is a rvalue), but it is a collection of characters, so how is it a char ? and if it is a char then why it is called string literal ? please explain. Thank you.
Tarun Jha wrote:
...but it is a collection of characters, so how is it a char ?
The variable
ptris a pointer to a collection ofchar-acters, be it 1 or 100.Tarun Jha wrote:
...then why it is called string literal ?
Like anything holding quotation marks apart, they are literally those characters. They haven't been modified, translated, obtained from some other place, coerced, etc. If you look inside the compiled file, you will see those characters, literally.
"One man's wage rise is another man's price increase." - Harold Wilson
"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons
"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles
-
#include
#include
using namespace std;int main(){
const char *ptr = "tarun" ;
//const string *name = "tarun";cout << name << endl ; return 0;}
in the above code if i assign a string literal to a const char*
Quote:
const string *name = "tarun";
it prints the string but the same with string gives error that
Quote:
cannot convert ‘const char’ to ‘const string
so it means any string literal is a const char (which i think is a rvalue), but it is a collection of characters, so how is it a char ? and if it is a char then why it is called string literal ? please explain. Thank you.
To me you are sort of asking a strange question well outside the literal string part, so lets just check you understand some basics First a string is class or if you want an object it has constructors, destructor and methods it isn't just an array of characters. string - C++ Reference[^] You can't remotely equate those two lines as anything similar, do you understand that? So with a string class when you declare it as a const (like your commented out) what are you expecting it will do? So you are clear you are asking for a constant pointer to an object and trying to set some literal string to that object. This may also help understand Victors response and David deals with the literal part. The point here is you can only create a string when it matches one of the constructor types of the class. What constructor functions exist controls how you can create it. Here is the examples of showing the seven standard constructor methods for the class string::string - C++ Reference[^] The situation with just a character array is very different
const char *ptr = "tarun";
We have a simple array of characters that can never be changed AKA they are constant Everything from a C to a C++ compiler understands the later because it's very trivial.
In vino veritas