Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

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explicit operator bool() const noexcept

Returns true if a value is present. Constexpr where possible. Alias for bool has_value() const noexcept .

Requires: Always available.

Complexity: Constant time.

Guarantees: Never throws an exception.

Last revised: January 31, 2019 at 01:07:35 UTC


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