C++ Greater Than Or Equal To

lhs >= rhs

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Technical Characteristics

• Return Type: bool (for built-in types).
• Associativity: Left-to-right.
• Precedence: Level 9. It binds less tightly than arithmetic operators (+, -, *, /) and bitwise shift operators (<<, >>), but more tightly than equality operators (==, !=) and logical operators (&&, ||).
• Usual Arithmetic Conversions: When comparing built-in numeric types of different sizes or domains, the compiler applies the usual arithmetic conversions to establish a common type before evaluating. This includes integral promotions (e.g., promoting a short to an int) or floating-point conversions (e.g., converting an int to a double).

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Pointer Comparison

• Both are null pointers.
• Both point to the exact same object or function.
• Both point to elements within the same array, or to one past the last element of that array.
• Both point to different non-static data members of the same object, provided they share the same access control (e.g., both public) and are not members of a union.

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Operator Overloading (Pre-C++20)

class Widget {
public:
    // Implemented using the less-than operator
    friend bool operator>=(const Widget& lhs, const Widget& rhs) {
        return !(lhs < rhs); 
    }
};

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C++20 Three-Way Comparison (<=>)

#include <compare>

class Widget {
public:
    // Compiler implicitly defaults == and resolves >= via expression rewriting
    auto operator<=>(const Widget&) const = default; 
};