explain the code please

[laura fidarova]

so i have a code here, could you please explain what these brackets do "{}" (not the ones after int main() but the ones as in sp{ test.find(' ') } etc )

also, what is "npos"?

 #include <string>
#include <iostream>
using namespace std;
int main()
{
	const string test{ "basketball is a popular sport" };
	string test1{ test };

	const auto sp{ test.find(' ') };

	if (sp != string::npos)
		test1.append(" ").append(test, 0, sp).erase(0, sp + 1);

	cout << test << '\n';
	cout << test1 << '\n';
}

[Repeater]

List initialisation. It's just a way to set the initial value of something.


const string test{ "basketball is a popular sport" };
This string's initial value is "basketball is a popular sport".

You'd get the same outcome here with
const string test = "basketball is a popular sport";


const auto sp{ test.find(' ') };
This creates an object of type <whatever string::find() returns>, initial value whatever comes back from the function call test.find(' ')

https://stackoverflow.com/questions/18222926/why-is-list-initialization-using-curly-braces-better-than-the-alternatives


string::npos is the special value returned by string::find if it didn't find what you're looking for.
https://www.cplusplus.com/reference/string/string/find/ (look at "Return Value" section).

[jlb]

In that content the braces are being used for Uniform Initialization, so that line is initializing the variable sp to the return value of the test.find(' ') function.

[laura fidarova]

thank you so much, this helped a lot!! :)