What is ${} ing called?

When we use ${} to display the value of any variable amidst text, what is the process called? Is it substituting or referencing?

Also, is there any such sign we can use in C++ while writing a program, inside the cout text?

Example:

int x=23;
cout<<"They have prepared ${x} cakes with honey and butter.";

Result: They have prepared 23 cakes with honey and butter.

Thanks.

It’s printing, though the scope is more limited to a single variable containing single or short string in this context.


Are we talking about ChoiceScript or C++ itself? I’m sure ${} is non-entity in C++.

I am talking about C++. Is there any substitute in C++ to use instead of ${} .

It’s been a long time since my last practice using C++, so a bit rusty here, but AFAI-can-tell that’s not how you print a text with variable between them.

int x=23;
cout << "They have prepared" << int << "cakes with honey and butter.";

https://www.w3schools.com/cpp/cpp_variables.asp


Otherwise, the good 'ol way

cout << "They have prepared";
cout << int;
cout << "cakes with honey and butter.";

Is there no way to print the variable directly inside the “text” part of cout without using <<int<<?

No. It’s part of C++ protocol. Keeping it short, C++ (and many other coding languages) uses a very specific syntax when handling certain datatypes.

Okay. Thanks.

This is an in-line string formatting. Most high level programming languages have this feature.

I don’t know much about C++, but in python it would be something like this:

var = 23
print(f"They have prepared {var} cakes with honey and butter.")

# or you could do the old way (before Python 3):

print("They have prepared {} cakes with honey and butter.".format(var))

In this post in StackOverflow, they use it like this for C++ 20:

#include <iostream>
#include <format>

int main() {
    std::cout << std::format("Hello {}!\n", "world");
}

So I guess to do what you want it would be something like:

#include <iostream>
#include <format>

int main() {
    int x=23;
    std::cout << std::format("They have prepared {} cakes with honey and butter.", x);
}

But don’t take my word for it.

I will try making a demo program with that. Even if it doesn’t work, thank you for taking the time.