Avoid storing std::span as class members

std::span is a non-owning view that doesn’t manage the lifetime of the data it references. Storing a span as a member creates a high risk of dangling references.

class RiskyClass {
    std::span<int> data_; // Dangerous!
public:
    RiskyClass(const std::vector<int>& vec) : data_(vec) {}
    // What happens when 'vec' goes out of scope?
};

Better alternatives

• Store the actual container
• Take span as function parameters only
• Use span for temporary operations within a single scope