Boost C++ Libraries

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This is an older version of Boost and was released in 2024. The current version is 1.89.0.

Function template operator<<

Function template operator<<

boost::operator<< — Provides streaming output for variant types.

Synopsis

// In header: <boost/variant/variant.hpp>


template<typename ElemType, typename Traits, typename T1, typename T2, ..., 
         typename TN> 
  std::basic_ostream<ElemType,Traits> & 
  operator<<(std::basic_ostream<ElemType,Traits> & out, 
             const variant<T1, T2, ..., TN> & rhs);

Description

Requires:	Every bounded type of the `variant` must fulfill the requirements of the OutputStreamable concept.
Effects:	Calls `out << x`, where `x` is the content of `rhs`.
Notes:	Not available when `BOOST_NO_IOSTREAM` is defined.