diff --git a/include/cpp2util.h b/include/cpp2util.h
index 2cb9ee1a8f..553f52e68a 100644
--- a/include/cpp2util.h
+++ b/include/cpp2util.h
@@ -894,6 +894,12 @@ inline constexpr auto is( auto const& x, auto const& value ) -> bool
     return false;
 }
 
+// Free function predicate case
+template< typename X >
+constexpr auto is( X const& x, bool (&value)(X const&) ) -> bool
+{
+    return value(x);
+}
 
 //-------------------------------------------------------------------------------------------------------------
 //  Built-in as
diff --git a/regression-tests/mixed-inspect-values-2.cpp2 b/regression-tests/mixed-inspect-values-2.cpp2
index ed250e52b0..e3e961dbb7 100644
--- a/regression-tests/mixed-inspect-values-2.cpp2
+++ b/regression-tests/mixed-inspect-values-2.cpp2
@@ -16,6 +16,10 @@ constexpr auto empty = [](auto&& x){
     return std::empty(x);
 };
 
+auto negative(auto v) {
+    return v < 0;
+}
+
 main: () -> int = {
     i := 15;
 
@@ -33,6 +37,12 @@ main: () -> int = {
         std::cout << "i is between 10 and 30" << std::endl;
     }
 
+    if i is (negative) {
+        std::cout << "i is negative" << std::endl;
+    } else {
+        std::cout << "i is not negative" << std::endl;
+    }
+
     v : std::vector<int> = ();
 
     if empty(v) {
diff --git a/regression-tests/test-results/apple-clang-14/mixed-inspect-values-2.cpp.execution b/regression-tests/test-results/apple-clang-14/mixed-inspect-values-2.cpp.execution
index 8372eadcae..43ab3e654f 100644
--- a/regression-tests/test-results/apple-clang-14/mixed-inspect-values-2.cpp.execution
+++ b/regression-tests/test-results/apple-clang-14/mixed-inspect-values-2.cpp.execution
@@ -1,5 +1,6 @@
 i is between 11 and 20
 less than 20
 i is between 10 and 30
+i is not negative
 v is empty
 v is empty
diff --git a/regression-tests/test-results/clang-12/mixed-inspect-values-2.cpp.execution b/regression-tests/test-results/clang-12/mixed-inspect-values-2.cpp.execution
index 8372eadcae..43ab3e654f 100644
--- a/regression-tests/test-results/clang-12/mixed-inspect-values-2.cpp.execution
+++ b/regression-tests/test-results/clang-12/mixed-inspect-values-2.cpp.execution
@@ -1,5 +1,6 @@
 i is between 11 and 20
 less than 20
 i is between 10 and 30
+i is not negative
 v is empty
 v is empty
diff --git a/regression-tests/test-results/mixed-inspect-values-2.cpp b/regression-tests/test-results/mixed-inspect-values-2.cpp
index 4b2cde6324..1f07be423f 100644
--- a/regression-tests/test-results/mixed-inspect-values-2.cpp
+++ b/regression-tests/test-results/mixed-inspect-values-2.cpp
@@ -27,14 +27,18 @@ constexpr auto empty = [](auto&& x){
     return std::empty(x);
 };
 
-#line 19 "mixed-inspect-values-2.cpp2"
+auto negative(auto v) {
+    return v < 0;
+}
+
+#line 23 "mixed-inspect-values-2.cpp2"
 [[nodiscard]] auto main() -> int;
     
 
 //=== Cpp2 function definitions =================================================
 
 
-#line 19 "mixed-inspect-values-2.cpp2"
+#line 23 "mixed-inspect-values-2.cpp2"
 [[nodiscard]] auto main() -> int{
     auto i {15}; 
 
@@ -48,10 +52,16 @@ constexpr auto empty = [](auto&& x){
         std::cout << "less than 20" << std::endl;
     }
 
-    if (cpp2::is(std::move(i), (in(10, 30)))) {
+    if (cpp2::is(i, (in(10, 30)))) {
         std::cout << "i is between 10 and 30" << std::endl;
     }
 
+    if (cpp2::is(std::move(i), (negative))) {
+        std::cout << "i is negative" << std::endl;
+    }else {
+        std::cout << "i is not negative" << std::endl;
+    }
+
     std::vector<int> v {}; 
 
     if (empty(v)) {