diff --git a/include/boost/lambda2/lambda2.hpp b/include/boost/lambda2/lambda2.hpp
index 87d7c3f..68009a0 100644
--- a/include/boost/lambda2/lambda2.hpp
+++ b/include/boost/lambda2/lambda2.hpp
@@ -8,6 +8,8 @@
 #include <functional>
 #include <type_traits>
 #include <utility>
+#include <tuple>
+#include <cstddef>
 
 // Same format as BOOST_VERSION:
 //   major * 100000 + minor * 100 + patch
@@ -22,6 +24,10 @@ namespace lambda2
 
 template<int I> struct lambda2_arg
 {
+    template<class... A> decltype(auto) operator()( A&&... a ) const noexcept
+    {
+        return std::get<std::size_t{I-1}>( std::tuple<A&&...>( std::forward<A>(a)... ) );
+    }
 };
 
 #if defined(__cpp_inline_variables) && __cpp_inline_variables >= 201606L
diff --git a/test/placeholders.cpp b/test/placeholders.cpp
index a29536d..61f8a27 100644
--- a/test/placeholders.cpp
+++ b/test/placeholders.cpp
@@ -25,5 +25,24 @@ int main()
     BOOST_TEST_EQ( std::bind(f, _8)( 1, 2, 3, 4, 5, 6, 7, 8 ), 8 );
     BOOST_TEST_EQ( std::bind(f, _9)( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 9 );
 
+    BOOST_TEST_EQ( _1( 1 ), 1 );
+    BOOST_TEST_EQ( _2( 1, 2 ), 2 );
+    BOOST_TEST_EQ( _3( 1, 2, 3 ), 3 );
+    BOOST_TEST_EQ( _4( 1, 2, 3, 4 ), 4 );
+    BOOST_TEST_EQ( _5( 1, 2, 3, 4, 5 ), 5 );
+    BOOST_TEST_EQ( _6( 1, 2, 3, 4, 5, 6 ), 6 );
+    BOOST_TEST_EQ( _7( 1, 2, 3, 4, 5, 6, 7 ), 7 );
+    BOOST_TEST_EQ( _8( 1, 2, 3, 4, 5, 6, 7, 8 ), 8 );
+    BOOST_TEST_EQ( _9( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 9 );
+
+    BOOST_TEST_EQ( _1( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 1 );
+    BOOST_TEST_EQ( _2( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 2 );
+    BOOST_TEST_EQ( _3( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 3 );
+    BOOST_TEST_EQ( _4( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 4 );
+    BOOST_TEST_EQ( _5( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 5 );
+    BOOST_TEST_EQ( _6( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 6 );
+    BOOST_TEST_EQ( _7( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 7 );
+    BOOST_TEST_EQ( _8( 1, 2, 3, 4, 5, 6, 7, 8, 9 ), 8 );
+
     return boost::report_errors();
 }