diff --git a/source/poodinis/autowire.d b/source/poodinis/autowire.d
index 22d0d29..80864aa 100644
--- a/source/poodinis/autowire.d
+++ b/source/poodinis/autowire.d
@@ -270,7 +270,7 @@ class AutowiredRegistration(RegistrationType : Object) : Registration {
             enum QualifiedName = fullyQualifiedName!RegistrationType ~ `.` ~ memberName;
             static if (__traits(compiles, __traits(getProtection, __traits(getMember, instance, memberName)))
                         && __traits(getProtection, __traits(getMember, instance, memberName)) == "public"
-                        && isFunction!(QualifiedName)
+                        && isFunction1!(mixin(QualifiedName))
                         && hasUDA!(__traits(getMember, instance, memberName), PreDestroy)) {
                 preDestructor = &__traits(getMember, instance, memberName);
             }
diff --git a/source/poodinis/container.d b/source/poodinis/container.d
index 5b0f759..47e8c95 100644
--- a/source/poodinis/container.d
+++ b/source/poodinis/container.d
@@ -443,7 +443,7 @@ synchronized class DependencyContainer {
             enum QualifiedName = fullyQualifiedName!Type ~ `.` ~ memberName;
             static if (__traits(compiles, __traits(getProtection, __traits(getMember, instance, memberName)))
                         && __traits(getProtection, __traits(getMember, instance, memberName)) == "public"
-                        && isFunction!(QualifiedName)
+                        && isFunction1!(mixin(QualifiedName))
                         && hasUDA!(__traits(getMember, instance, memberName), PostConstruct)) {
                 __traits(getMember, instance, memberName)();
             }
diff --git a/source/poodinis/polyfill.d b/source/poodinis/polyfill.d
index 0d6dc99..33d5d2a 100644
--- a/source/poodinis/polyfill.d
+++ b/source/poodinis/polyfill.d
@@ -43,21 +43,24 @@ static if (!__traits(compiles, basicExceptionCtors)) {
     }
 }
 
-static if (!__traits(compiles, isFunction)) {
-    template isFunction(X...) if (X.length == 1)
+static if (!__traits(compiles, isFunction1)) {
+    template isFunction1(X...) 
     {
+        static if (X.length > 1) {
+            enum isFunction1 = false;
+        } else
         static if (is(typeof(&X[0]) U : U*) && is(U == function) ||
                     is(typeof(&X[0]) U == delegate))
         {
             // x is a (nested) function symbol.
-            enum isFunction = true;
+            enum isFunction1 = true;
         }
         else static if (is(X[0] T))
         {
             // x is a type.  Take the type of it and examine.
-            enum isFunction = is(T == function);
+            enum isFunction1 = is(T == function);
         }
         else
-            enum isFunction = false;
+            enum isFunction1 = false;
     }
 }