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C++ std::optional

C++ reference for c++ std::optional.

Syntax

#include <optional>
std::optional<int> score = 9;
if (score) { /* *score */ }

Examples

C++ std::optional example

A focused example you can adapt while practising.

#include <optional>
std::optional<int> score = 9;
if (score) { /* *score */ }

Best practices

  • Start with the smallest working example, then adapt it to your project.
  • Use the language’s standard library and idioms before introducing extra dependencies.

At a glance

Purpose
Systems and general-purpose software
File extension
.cpp · .hpp
Runs in
Compiled native applications
Usually used with
Compiler and standard library

Specifications & further reading

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