diff --git a/boost/yap/config.hpp b/boost/yap/config.hpp
new file mode 100644
index 0000000..35f7000
--- /dev/null
+++ b/boost/yap/config.hpp
@@ -0,0 +1,18 @@
+#ifndef BOOST_YAP_CONFIG_HPP_INCLUDED
+#define BOOST_YAP_CONFIG_HPP_INCLUDED
+
+
+#ifndef BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+/** Controls whether a conversion operator template is defined for
+    <code>expression<></code>.
+
+    Default value is <code>0</code>.
+
+    This is useful when you want to have <code>expression<></code>s
+    auto-evaluated on assignment to non-<code>yap</code> types.  It can also
+    wreak havok on your code due to unintentional implicit conversions.  Here
+    be dragons. */
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 0
+#endif
+
+#endif
diff --git a/boost/yap/expression.hpp b/boost/yap/expression.hpp
index 2a74d82..8ad3f20 100644
--- a/boost/yap/expression.hpp
+++ b/boost/yap/expression.hpp
@@ -126,13 +126,13 @@ namespace boost { namespace yap {
 
         tuple_type elements;
 
-#if defined(BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE) || defined(BOOST_YAP_DOXYGEN)
+#if BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE || defined(BOOST_YAP_DOXYGEN)
         /** Conversion operator.  Attempts to convert \c *this to any type \a
             R with a call to the <code>eval_expression_as()</code>
             customization point.  This function is only defined if the
             configuration macro
             <code>BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE</code> has been
-            defined by the user. */ // TODO: customization points need documentation.
+            defined by the user to be nonzero. */ // TODO: customization points need documentation.
         template <typename R>
         operator R ()
         { return eval_expression_as(*this, hana::basic_type<R>{}); }
@@ -375,13 +375,13 @@ namespace boost { namespace yap {
 
         tuple_type elements;
 
-#if defined(BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE) || defined(BOOST_YAP_DOXYGEN)
+#if BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE || defined(BOOST_YAP_DOXYGEN)
         /** Conversion operator.  Attempts to convert \c *this to any type \a
             R with a call to the <code>eval_expression_as()</code>
             cutomization point.  This function is only defined if the
             configuration macro
             <code>BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE</code> has been
-            defined by the user. */ // TODO
+            defined by the user to be nonzero. */ // TODO
         template <typename R>
         operator R ()
         { return eval_expression_as(*this, hana::basic_type<R>{}); }
@@ -779,125 +779,6 @@ namespace boost { namespace yap {
         }
     }
 
-#ifdef BOOST_YAP_DOXYGEN
-
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator<< (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator>> (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator* (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator/ (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator% (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator+ (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator- (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator< (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator> (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator<= (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator>= (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator== (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator!= (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator|| (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator&& (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator& (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator| (T && lhs, Expr && rhs);
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION is not.  \see
-        BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
-    template <typename T, typename Expr> auto operator^ (T && lhs, Expr && rhs);
-
-    /** Only defined when the configuration macro
-        BOOST_YAP_NO_EXPR_IF_ELSE_FOR_EXPRESSION is not. \see
-        BOOST_YAP_USER_EXPR_IF_ELSE for full semantics. */
-    template <typename Expr1, typename Expr2, typename Expr3>
-    auto if_else (Expr1 && expr1, Expr2 && expr2, Expr3 && expr3);
-
-#else
-
-#ifndef BOOST_YAP_NO_FREE_OPERATORS_FOR_EXPRESSION
-
-#define BOOST_YAP_BINARY_FREE_OPERATOR(op_name)                     \
-    BOOST_YAP_USER_FREE_BINARY_OPERATOR(op_name, expression)
-
-    BOOST_YAP_BINARY_FREE_OPERATOR(shift_left) // <<
-    BOOST_YAP_BINARY_FREE_OPERATOR(shift_right) // >>
-    BOOST_YAP_BINARY_FREE_OPERATOR(multiplies) // *
-    BOOST_YAP_BINARY_FREE_OPERATOR(divides) // /
-    BOOST_YAP_BINARY_FREE_OPERATOR(modulus) // %
-    BOOST_YAP_BINARY_FREE_OPERATOR(plus) // +
-    BOOST_YAP_BINARY_FREE_OPERATOR(minus) // -
-    BOOST_YAP_BINARY_FREE_OPERATOR(less) // <
-    BOOST_YAP_BINARY_FREE_OPERATOR(greater) // >
-    BOOST_YAP_BINARY_FREE_OPERATOR(less_equal) // <=
-    BOOST_YAP_BINARY_FREE_OPERATOR(greater_equal) // >=
-    BOOST_YAP_BINARY_FREE_OPERATOR(equal_to) // ==
-    BOOST_YAP_BINARY_FREE_OPERATOR(not_equal_to) // !=
-    BOOST_YAP_BINARY_FREE_OPERATOR(logical_or) // ||
-    BOOST_YAP_BINARY_FREE_OPERATOR(logical_and) // &&
-    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_and) // &
-    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_or) // |
-    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_xor) // ^
-
-#undef BOOST_YAP_BINARY_FREE_OPERATOR
-
-#endif
-
-#ifndef BOOST_YAP_NO_EXPR_IF_ELSE_FOR_EXPRESSION
-
-    BOOST_YAP_USER_EXPR_IF_ELSE(::boost::yap::expression)
-
-#endif
-
-#endif // BOOST_YAP_DOXYGEN
-
     /** Makes a new expression instantiated from the expression template \a
         ExprTemplate, of kind \a Kind, with the given values as its elements.
 
diff --git a/boost/yap/expression_free_operators.hpp b/boost/yap/expression_free_operators.hpp
new file mode 100644
index 0000000..d332c91
--- /dev/null
+++ b/boost/yap/expression_free_operators.hpp
@@ -0,0 +1,76 @@
+#ifndef BOOST_YAP_EXPRESSION_FREE_OPERATORS_HPP_INCLUDED
+#define BOOST_YAP_EXPRESSION_FREE_OPERATORS_HPP_INCLUDED
+
+
+namespace boost { namespace yap {
+
+#ifndef BOOST_YAP_DOXYGEN
+
+#define BOOST_YAP_BINARY_FREE_OPERATOR(op_name)                     \
+    BOOST_YAP_USER_FREE_BINARY_OPERATOR(op_name, expression)
+
+    BOOST_YAP_BINARY_FREE_OPERATOR(shift_left) // <<
+    BOOST_YAP_BINARY_FREE_OPERATOR(shift_right) // >>
+    BOOST_YAP_BINARY_FREE_OPERATOR(multiplies) // *
+    BOOST_YAP_BINARY_FREE_OPERATOR(divides) // /
+    BOOST_YAP_BINARY_FREE_OPERATOR(modulus) // %
+    BOOST_YAP_BINARY_FREE_OPERATOR(plus) // +
+    BOOST_YAP_BINARY_FREE_OPERATOR(minus) // -
+    BOOST_YAP_BINARY_FREE_OPERATOR(less) // <
+    BOOST_YAP_BINARY_FREE_OPERATOR(greater) // >
+    BOOST_YAP_BINARY_FREE_OPERATOR(less_equal) // <=
+    BOOST_YAP_BINARY_FREE_OPERATOR(greater_equal) // >=
+    BOOST_YAP_BINARY_FREE_OPERATOR(equal_to) // ==
+    BOOST_YAP_BINARY_FREE_OPERATOR(not_equal_to) // !=
+    BOOST_YAP_BINARY_FREE_OPERATOR(logical_or) // ||
+    BOOST_YAP_BINARY_FREE_OPERATOR(logical_and) // &&
+    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_and) // &
+    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_or) // |
+    BOOST_YAP_BINARY_FREE_OPERATOR(bitwise_xor) // ^
+
+#undef BOOST_YAP_BINARY_FREE_OPERATOR
+
+#else
+
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator<< (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator>> (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator* (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator/ (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator% (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator+ (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator- (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator< (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator> (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator<= (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator>= (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator== (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator!= (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator|| (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator&& (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator& (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator| (T && lhs, Expr && rhs);
+    /** \see BOOST_YAP_USER_FREE_BINARY_OPERATOR for full semantics. */
+    template <typename T, typename Expr> auto operator^ (T && lhs, Expr && rhs);
+
+#endif // BOOST_YAP_DOXYGEN
+
+} }
+
+#endif
diff --git a/boost/yap/expression_fwd.hpp b/boost/yap/expression_fwd.hpp
index 06dddd2..8039959 100644
--- a/boost/yap/expression_fwd.hpp
+++ b/boost/yap/expression_fwd.hpp
@@ -1,6 +1,8 @@
 #ifndef BOOST_YAP_EXPRESSION_FWD_HPP_INCLUDED
 #define BOOST_YAP_EXPRESSION_FWD_HPP_INCLUDED
 
+#include <boost/yap/config.hpp>
+
 #include <boost/hana/integral_constant.hpp>
 #include <boost/hana/tuple.hpp>
 
diff --git a/boost/yap/expression_if_else.hpp b/boost/yap/expression_if_else.hpp
new file mode 100644
index 0000000..9ad5898
--- /dev/null
+++ b/boost/yap/expression_if_else.hpp
@@ -0,0 +1,21 @@
+#ifndef BOOST_YAP_EXPRESSION_IF_ELSE_HPP_INCLUDED
+#define BOOST_YAP_EXPRESSION_IF_ELSE_HPP_INCLUDED
+
+
+namespace boost { namespace yap {
+
+#ifndef BOOST_YAP_DOXYGEN
+
+    BOOST_YAP_USER_EXPR_IF_ELSE(::boost::yap::expression)
+
+#else
+
+    /** \see BOOST_YAP_USER_EXPR_IF_ELSE for full semantics. */
+    template <typename Expr1, typename Expr2, typename Expr3>
+    auto if_else (Expr1 && expr1, Expr2 && expr2, Expr3 && expr3);
+
+#endif
+
+} }
+
+#endif
diff --git a/boost/yap/yap.hpp b/boost/yap/yap.hpp
new file mode 100644
index 0000000..2fb3c14
--- /dev/null
+++ b/boost/yap/yap.hpp
@@ -0,0 +1,10 @@
+#ifndef BOOST_YAP_YAP_HPP_INCLUDED
+#define BOOST_YAP_YAP_HPP_INCLUDED
+
+
+#include <boost/yap/expression.hpp>
+#include <boost/yap/expression_free_operators.hpp>
+#include <boost/yap/expression_if_else.hpp>
+#include <boost/yap/print.hpp>
+
+#endif
diff --git a/example/lazy_vector.cpp b/example/lazy_vector.cpp
index 77900ec..4982d3a 100644
--- a/example/lazy_vector.cpp
+++ b/example/lazy_vector.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <algorithm>
diff --git a/example/mixed.cpp b/example/mixed.cpp
index 7be0e8e..808312f 100644
--- a/example/mixed.cpp
+++ b/example/mixed.cpp
@@ -1,4 +1,4 @@
-#include <boost/yap/expression.hpp>
+#include <boost/yap/yap.hpp>
 
 #include <complex>
 #include <list>
diff --git a/example/vec3.cpp b/example/vec3.cpp
index 392d62e..358afe2 100644
--- a/example/vec3.cpp
+++ b/example/vec3.cpp
@@ -1,4 +1,4 @@
-#include <boost/yap/expression.hpp>
+#include <boost/yap/yap.hpp>
 
 #include <array>
 #include <iostream>
diff --git a/example/vector.cpp b/example/vector.cpp
index 971c4d3..b672dfd 100644
--- a/example/vector.cpp
+++ b/example/vector.cpp
@@ -1,4 +1,4 @@
-#include <boost/yap/expression.hpp>
+#include <boost/yap/yap.hpp>
 
 #include <vector>
 #include <iostream>
diff --git a/perf/code_gen_samples.cpp b/perf/code_gen_samples.cpp
index 3d0897c..5bf78cc 100644
--- a/perf/code_gen_samples.cpp
+++ b/perf/code_gen_samples.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 
diff --git a/test/call_expr_implicit.cpp b/test/call_expr_implicit.cpp
index 4146f1d..ac7249d 100644
--- a/test/call_expr_implicit.cpp
+++ b/test/call_expr_implicit.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/compile_x_plus_term.cpp b/test/compile_x_plus_term.cpp
index 08eb89c..345e939 100644
--- a/test/compile_x_plus_term.cpp
+++ b/test/compile_x_plus_term.cpp
@@ -1,4 +1,5 @@
 #include <boost/yap/expression.hpp>
+#include <boost/yap/expression_free_operators.hpp>
 
 #include <string>
 
diff --git a/test/default_eval.cpp b/test/default_eval.cpp
index ccb7fd4..e4178f5 100644
--- a/test/default_eval.cpp
+++ b/test/default_eval.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/depth_stress_test_left.cpp b/test/depth_stress_test_left.cpp
index c2860c2..fb0e3d3 100644
--- a/test/depth_stress_test_left.cpp
+++ b/test/depth_stress_test_left.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/depth_stress_test_right.cpp b/test/depth_stress_test_right.cpp
index 62e6019..3717311 100644
--- a/test/depth_stress_test_right.cpp
+++ b/test/depth_stress_test_right.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/lazy_vector_alloc_test.cpp b/test/lazy_vector_alloc_test.cpp
index 421d3dd..81884e9 100644
--- a/test/lazy_vector_alloc_test.cpp
+++ b/test/lazy_vector_alloc_test.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <algorithm>
diff --git a/test/reference_returns.cpp b/test/reference_returns.cpp
index 8228384..7a21f71 100644
--- a/test/reference_returns.cpp
+++ b/test/reference_returns.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/user_eval_expression_as.cpp b/test/user_eval_expression_as.cpp
index a0c4b1d..de2773f 100644
--- a/test/user_eval_expression_as.cpp
+++ b/test/user_eval_expression_as.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/user_expression_transform.cpp b/test/user_expression_transform.cpp
index df068cd..c4e2bcf 100644
--- a/test/user_expression_transform.cpp
+++ b/test/user_expression_transform.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/user_expression_transform_2.cpp b/test/user_expression_transform_2.cpp
index f79fb60..5d51e40 100644
--- a/test/user_expression_transform_2.cpp
+++ b/test/user_expression_transform_2.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/user_expression_transform_3.cpp b/test/user_expression_transform_3.cpp
index b09a79a..8ae3282 100644
--- a/test/user_expression_transform_3.cpp
+++ b/test/user_expression_transform_3.cpp
@@ -1,4 +1,6 @@
 #include <boost/yap/expression.hpp>
+#include <boost/yap/expression_free_operators.hpp>
+#include <boost/yap/expression_if_else.hpp>
 
 #include <gtest/gtest.h>
 
diff --git a/test/user_operator_and_eval_expression_as.cpp b/test/user_operator_and_eval_expression_as.cpp
index f0ce751..cfbe042 100644
--- a/test/user_operator_and_eval_expression_as.cpp
+++ b/test/user_operator_and_eval_expression_as.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>
diff --git a/test/user_operator_eval.cpp b/test/user_operator_eval.cpp
index 48385d5..5ea9e5e 100644
--- a/test/user_operator_eval.cpp
+++ b/test/user_operator_eval.cpp
@@ -1,4 +1,4 @@
-#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE
+#define BOOST_YAP_CONVERSION_OPERATOR_TEMPLATE 1
 #include <boost/yap/expression.hpp>
 
 #include <gtest/gtest.h>