1 files changed, 65 insertions, 0 deletions
diff --git a/test/typeparam/issue51303.go b/test/typeparam/issue51303.go
new file mode 100644
index 0000000..a3a7849
--- /dev/null
+++ b/test/typeparam/issue51303.go
@@ -0,0 +1,65 @@
+// run
+
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	x := [][]int{{1}}
+	y := [][]int{{2, 3}}
+	IntersectSS(x, y)
+}
+
+type list[E any] interface {
+	~[]E
+	Equal(x, y E) bool
+}
+
+// ss is a set of sets
+type ss[E comparable, T []E] []T
+
+func (ss[E, T]) Equal(a, b T) bool {
+	return SetEq(a, b)
+}
+
+func IntersectSS[E comparable](x, y [][]E) [][]E {
+	return IntersectT[[]E, ss[E, []E]](ss[E, []E](x), ss[E, []E](y))
+}
+
+func IntersectT[E any, L list[E]](x, y L) L {
+	var z L
+outer:
+	for _, xe := range x {
+		fmt.Println("xe", xe)
+		for _, ye := range y {
+			fmt.Println("ye", ye)
+			fmt.Println("x", x)
+			if x.Equal(xe, ye) {
+				fmt.Println("appending")
+				z = append(z, xe)
+				continue outer
+			}
+		}
+	}
+	return z
+}
+
+func SetEq[S []E, E comparable](x, y S) bool {
+	fmt.Println("SetEq", x, y)
+outer:
+	for _, xe := range x {
+		for _, ye := range y {
+			if xe == ye {
+				continue outer
+			}
+		}
+		return false // xs wasn't found in y
+	}
+	return true
+}