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

Function template callable

boost::yap::callable

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


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

Returns the callable in a call expression.

Equivalent to get(expr, 0).

	Note
	`callable()` is only valid if Expr is an `expr_kind::call` expression.