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diff --git a/Examples/test-suite/cpp11_template_parameters_decltype.i b/Examples/test-suite/cpp11_template_parameters_decltype.i
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+++ b/Examples/test-suite/cpp11_template_parameters_decltype.i
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+%module cpp11_template_parameters_decltype
+
+%inline %{
+// Github issue #1589
+template <decltype(true) X = true>
+void A() { }
+%}
+
+// %template(A) A<>; // not working
+%template(A) A<true>; // workaround
+
+
+%include <std_string.i>
+%include <std_vector.i>
+%include <std_map.i>
+
+#pragma SWIG nowarn=SWIGWARN_CPP11_DECLTYPE
+
+%{
+// Simple implementation of helper functions required in test below
+std::string array(std::vector<std::string>::const_iterator begin, std::vector<std::string>::const_iterator end) {
+  return "not implemented";
+}
+std::string object(std::map<std::string, std::string>::const_iterator begin, std::map<std::string, std::string>::const_iterator end) {
+  return "not implemented";
+}
+%}
+
+%inline %{
+#include <iostream>
+
+// Github issue #1590
+struct Converter {
+  std::string to_json() const { return std::string(); }
+};
+struct Json {
+  int ctor;
+  Json(std::string s) : ctor(0) {}
+  template < class T, class = decltype(&T::to_json) >
+    Json(const T & t) : Json(t.to_json()) { ctor = 1; }
+
+// Github issue #1589
+  // Implicit constructor: map-like objects (std::map, std::unordered_map, etc)
+  template <class M, typename std::enable_if<
+      std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value,
+      int>::type = 0>
+          Json(const M & m) : Json(object(m.begin(), m.end())) { ctor = 2; }
+  // Implicit constructor: vector-like objects (std::list, std::vector, std::set, etc)
+  template <class V, typename std::enable_if<
+      std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
+          int>::type = 0>
+  Json(const V & v) : Json(array(v.begin(), v.end())) { ctor = 3; }
+
+  // Same sort of thing as constructors above but for a member function
+  int mmm(std::string s) { return 100; }
+  template < class T, class = decltype(&T::to_json) >
+    int mmm(const T & t) { return 101; }
+  template <class M, typename std::enable_if<
+    std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value,
+    int>::type = 0>
+      int mmm(const M & m) { return 102; }
+  template <class V, typename std::enable_if<
+    std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
+    int>::type = 0>
+      int mmm(const V & v) { return 103; }
+};
+
+void tester(bool show) {
+  // Example usage from c++
+  if (show) {
+    Json json0(std::string("hi"));
+    Converter converter;
+    std::cout << "json0 " << json0.ctor << std::endl;
+    Json json1 = Json(converter);
+    std::cout << "json1 " << json1.ctor << std::endl;
+    std::map<std::string, std::string> myStringStringMap;
+    Json json2 = Json(myStringStringMap);
+    std::cout << "json2 " << json2.ctor << std::endl;
+    std::vector<std::string> myVectorString;
+    Json json3 = Json(myVectorString);
+    std::cout << "json3 " << json3.ctor << std::endl;
+
+    std::cout << "json0.mmm " << json0.mmm("bye") << std::endl;
+    std::cout << "json1.mmm " << json1.mmm(converter) << std::endl;
+    std::cout << "json2.mmm " << json2.mmm(myStringStringMap) << std::endl;
+    std::cout << "json3.mmm " << json3.mmm(myVectorString) << std::endl;
+  }
+}
+%}
+
+%template(VectorString) std::vector<std::string>;
+%template(MapStringString) std::map<std::string, std::string>;
+
+// There is quite a bit of inconsistency about providing or not providing default
+// template parameters that needs investigating. Below is a combination that works.
+
+// Note that instantiating the two Json constructors (or the two mmm methods) that
+// use enable_if is ambiguous given the enable_if is not evaluated by SWIG.
+
+// %template(Json) Json::Json<Converter>; // not working
+%template(Json) Json::Json<Converter, std::string>; // workaround
+%template(Json) Json::Json<std::map<std::string, std::string>, 0>;
+%template(Json) Json::Json<std::vector<std::string>, 0>;
+
+%template(mmm) Json::mmm<Converter, std::string>;
+%template(mmm) Json::mmm<std::map<std::string, std::string>, 0>;
+%template(mmm) Json::mmm<std::vector<std::string>, 0>;