std::islessgreater(3)

✨ std::islessgreater(3) — C++ Standard Libary ✨

okay so bestie, we're looking at std::islessgreater(3) from the C++ Standard Libary, and it's lowkey a tiny page with a very specific job. Let's get into it 🫶

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🌸 NAME 🌸

std::islessgreater — std::islessgreater.

Yes, that's the whole name section, and it ate. 💅

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🎀 Synopsis 🎀

Defined in header <cmath>:

bool islessgreater( float x, float y );

(since C++11)

bool islessgreater( double x, double y );

(until C++23)

bool islessgreater( long double x, long double y );

constexpr bool islessgreater( /* floating-point-type */ x,
                              /* floating-point-type */ y );

(1) (since C++23)

💫 Additional overloads 💫

Defined in header <cmath>:

template< class Arithmetic1, class Arithmetic2 >
bool islessgreater( Arithmetic1 x, Arithmetic2 y );

(A) (since C++11) (constexpr since C++23)

1) Determines if the floating point number x is less than or greater than the floating-point number y, without setting floating-point exceptions. The library provides overloads for all cv-unqualified floating-point types as the type of the parameters x and y. (since C++23)

A) Additional overloads are provided for all other combinations of arithmetic types.

🧮 Parameters 🧮

• x, y — floating-point or integer values. ✨

✅ Return value ✅

true if x < y || x > y, false otherwise. That's it, that's the return value, no cap. 🫶

📝 Notes 📝

The built-in operator< and operator> for floating-point numbers may raise FE_INVALID if one or both of the arguments is NaN. This function is a "quiet" version of the expression x < y || x > y. 😌

⚠️ bestie, this is the caveat: the built-ins can raise FE_INVALID when NaN is in the mix, and this function is the quiet version.

The additional overloads are not required to be provided exactly as (A). They only need to be sufficient to ensure that for their first argument num1 and second argument num2:

• If num1 or num2 has type long double, then std::islessgreater(num1, num2) has the same effect as std::islessgreater(static_cast<long double>(num1), static_cast<long double>(num2)).
• Otherwise, if num1 and/or num2 has type double or an integer type, then std::islessgreater(num1, num2) has the same effect as std::islessgreater(static_cast<double>(num1), static_cast<double>(num2)). (until C++23)
• Otherwise, if num1 or num2 has type float, then std::islessgreater(num1, num2) has the same effect as std::islessgreater(static_cast<float>(num1), static_cast<float>(num2)).

If num1 and num2 have arithmetic types, then std::islessgreater(num1, num2) has the same effect as std::islessgreater(static_cast</* common-floating-point-type */>(num1), static_cast</* common-floating-point-type */>(num2)), where /* common-floating-point-type */ is the floating-point type with the greatest floating-point conversion rank and greatest floating-point conversion subrank between the types of num1 and num2, arguments of integer type are considered to have the same floating-point conversion rank as double. (since C++23)

If no such floating-point type with the greatest rank and subrank exists, then overload resolution does not result in a usable candidate from the overloads provided.

👀 See also 👀

• isless — checks if the first floating-point argument is less than the second (C++11) (function)
• isgreater — checks if the first floating-point argument is greater than the second (C++11) (function)
• C documentation for islessgreater

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that's the whole page, bestie 💖 source/version/date tea: http://cppreference.com, 2024.06.10, and this page is std::islessgreater(3). mwah 💋