std::left,s...d::internal(3)

💖 NAME 💖

okay bestie, real talk: this page is std::left,s...d::internal(3) from the C++ Standard Libary manual — yes, that's the manual name exactly, typo and all 😭 we respect the source.

• std::left,std::right,std::internal — std::left,std::right,std::internal (the NAME line said it twice, so I'm giving you both, no cap)

✨ Synopsis ✨

Defined in header <ios>:

std::ios_base& left( std::ios_base& str );     (1)
std::ios_base& right( std::ios_base& str );    (2)
std::ios_base& internal( std::ios_base& str ); (3)

So this whole situation modifies the positioning of the fill characters in an output stream. left and right apply to any type being output, while internal applies to integer, floating-point, and monetary output. And it has no effect on input, periodt.

1. Sets the adjustfield of the stream str to left as if by calling str.setf(std::ios_base::left, std::ios_base::adjustfield).
2. Sets the adjustfield of the stream str to right as if by calling str.setf(std::ios_base::right, std::ios_base::adjustfield).
3. Sets the adjustfield of the stream str to internal as if by calling str.setf(std::ios_base::internal, std::ios_base::adjustfield).

The initial default for standard streams is equivalent to right. That's the vibe out of the box, no cap.

This is an I/O manipulator. It may be called with an expression such as out << std::left for any out of type std::basic_ostream, or with an expression such as in >> std::left for any in of type std::basic_istream.

🎀 Parameters 🎀

• str — reference to I/O stream

🌸 Return value 🌸

str (reference to the stream after manipulation). She hands you the stream back after she's done styling it, bestie 🫶

🦋 Example 🦋

// Run this code

#include <iomanip>
#include <iostream>
#include <locale>

int main()
{
    std::cout.imbue(std::locale("en_US.utf8"));

    std::cout << "Default positioning:\n" << std::setfill('*')
              << std::setw(12) << -1.23  << '\n'
              << std::setw(12) << std::hex << std::showbase << 42 <<
       '\n'
              << std::setw(12) << std::put_money(123, true) << "\n\n";

    std::cout << "Left positioning:\n" << std::left
              << std::setw(12) << -1.23  << '\n'
              << std::setw(12) << 42 << '\n'
              << std::setw(12) << std::put_money(123, true) << "\n\n";

    std::cout << "Internal positioning:\n" << std::internal
              << std::setw(12) << -1.23  << '\n'
              << std::setw(12) << 42 << '\n'
              << std::setw(12) << std::put_money(123, true) << "\n\n";

    std::cout << "Right positioning:\n" << std::right
              << std::setw(12) << -1.23  << '\n'
              << std::setw(12) << 42 << '\n'
              << std::setw(12) << std::put_money(123, true) << '\n';
}

Output:

Default positioning:
*******-1.23
********0x2a
***USD *1.23

Left positioning:
-1.23*******
0x2a********
USD *1.23***

Internal positioning:
-*******1.23
0x********2a
USD ****1.23

Right positioning:
*******-1.23
********0x2a
***USD *1.23

👑 See also 👑

• setw — changes the width of the next input/output field (function)
• setfill — changes the fill character (function template)
• showbase — controls whether prefix is used to indicate numeric base
• noshowbase — (function)

okay that's the whole page, bestie 🫶✨ source: http://cppreference.com, version/date: 2024.06.10, page: std::left,s...d::internal(3). Now go make those fill characters sit exactly where you want them 💅🔥