A value-semantic, type-safe wrapper for representing 'optional' (or 'nullable') objects of a given type. An optional object may or may not contain a value of the underlying type.

The Boost Iterator Library contains two parts. The first is a system of concepts which extend the C++ standard iterator requirements.

A new infrastructure for generic algorithms that builds on top of the new iterator concepts.

Serialization for persistence and marshalling.

LL parser framework represents parsers directly as EBNF grammars in inlined C++.

Portable C++ multi-threading. C++03, C++11, C++14, C++17.