Optional

A single-header header-only library for representing optional (nullable) objects for C++14 (and C++11 to some extent) and passing them by value.

Used in the Mapbox GL plugin of Qt Location.

The sources can be found in reproducible-path/qtlocation-opensource-src-5.15.8+dfsg/src/3rdparty/mapbox-gl-native/deps/optional.

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 Copyright (C) 2011 - 2012 Andrzej Krzemienski

Boost Software License 1.0.

 Boost Software License - Version 1.0 - August 17th, 2003

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