Boost C++ Libraries

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Function template then

boost::yap::then

// In header: <boost/yap/algorithm.hpp>


template<typename Expr> constexpr decltype(auto) then(Expr && expr);

Returns the then-expression in an if_else expression.

Equivalent to get(expr, 1_c).

	Note
	`then()` is only valid if Expr is an `expr_kind::if_else` expression.