Snippet

Functional Error Handling with Optional

std::optional represents a value that might or might not exist. It is a safer alternative to returning magic numbers (like -1) or null pointers, forcing the caller to explicitly check if a value is present.

snippet.cpp

cpp

#include <iostream>
#include <optional>
 
std::optional<int> find_even(int value) {
    if (value % 2 == 0) return value;
    return std::nullopt;
}
 
int main() {
    auto result = find_even(7);
 
    if (result.has_value()) {
        std::cout << "Found: " << *result << std::endl;
    } else {
        std::cout << "No even value found." << std::endl;
    }
 
    // Using value_or for a default fallback
    std::cout << "Result or default: " << find_even(3).value_or(0) << std::endl;
    return 0;
}

Breakdown

return std::nullopt;

Explicitly returns a 'no-value' state to indicate failure or absence.

find_even(3).value_or(0)

Returns the contained value if present, otherwise returns the provided default (0).

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Functional Error Handling with Optional

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