Conditional Variable Scope Limiting

Snippet

Conditional Variable Scope Limiting

C++17 introduced selection statements with initializers. This allows you to initialize a variable within the if-statement scope, keeping the namespace clean and preventing accidental reuse of loop/iterator variables.

snippet.cpp

cpp

#include <iostream>
#include <vector>
 
int main() {
    std::vector<int> nums = {1, 2, 3};
 
    if (auto it = nums.begin(); it != nums.end()) {
        std::cout << "First element: " << *it << std::endl;
    }
    // 'it' is not accessible here
    return 0;
}

Breakdown

if (auto it = nums.begin(); it != nums.end())

Initializes 'it' and checks the condition in a single line; 'it' is valid only inside the if/else block.

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Conditional Variable Scope Limiting

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