1 files changed, 103 insertions, 0 deletions
diff --git a/test/typeparam/list.go b/test/typeparam/list.go
new file mode 100644
index 0000000..34ad71c
--- /dev/null
+++ b/test/typeparam/list.go
@@ -0,0 +1,103 @@
+// run
+
+// Copyright 2021 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"
+)
+
+type Ordered interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64 |
+		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+		~float32 | ~float64 |
+		~string
+}
+
+// _List is a linked list of ordered values of type T.
+type _List[T Ordered] struct {
+	next *_List[T]
+	val  T
+}
+
+func (l *_List[T]) Largest() T {
+	var max T
+	for p := l; p != nil; p = p.next {
+		if p.val > max {
+			max = p.val
+		}
+	}
+	return max
+}
+
+type OrderedNum interface {
+	~int | ~int8 | ~int16 | ~int32 | ~int64 |
+		~uint | ~uint8 | ~uint16 | ~uint32 | ~uint64 | ~uintptr |
+		~float32 | ~float64
+}
+
+// _ListNum is a linked _List of ordered numeric values of type T.
+type _ListNum[T OrderedNum] struct {
+	next *_ListNum[T]
+	val  T
+}
+
+const Clip = 5
+
+// ClippedLargest returns the largest in the list of OrderNums, but a max of 5.
+// Test use of untyped constant in an expression with a generically-typed parameter
+func (l *_ListNum[T]) ClippedLargest() T {
+	var max T
+	for p := l; p != nil; p = p.next {
+		if p.val > max && p.val < Clip {
+			max = p.val
+		}
+	}
+	return max
+}
+
+func main() {
+	i3 := &_List[int]{nil, 1}
+	i2 := &_List[int]{i3, 3}
+	i1 := &_List[int]{i2, 2}
+	if got, want := i1.Largest(), 3; got != want {
+		panic(fmt.Sprintf("got %d, want %d", got, want))
+	}
+
+	b3 := &_List[byte]{nil, byte(1)}
+	b2 := &_List[byte]{b3, byte(3)}
+	b1 := &_List[byte]{b2, byte(2)}
+	if got, want := b1.Largest(), byte(3); got != want {
+		panic(fmt.Sprintf("got %d, want %d", got, want))
+	}
+
+	f3 := &_List[float64]{nil, 13.5}
+	f2 := &_List[float64]{f3, 1.2}
+	f1 := &_List[float64]{f2, 4.5}
+	if got, want := f1.Largest(), 13.5; got != want {
+		panic(fmt.Sprintf("got %f, want %f", got, want))
+	}
+
+	s3 := &_List[string]{nil, "dd"}
+	s2 := &_List[string]{s3, "aa"}
+	s1 := &_List[string]{s2, "bb"}
+	if got, want := s1.Largest(), "dd"; got != want {
+		panic(fmt.Sprintf("got %s, want %s", got, want))
+	}
+
+	j3 := &_ListNum[int]{nil, 1}
+	j2 := &_ListNum[int]{j3, 32}
+	j1 := &_ListNum[int]{j2, 2}
+	if got, want := j1.ClippedLargest(), 2; got != want {
+		panic(fmt.Sprintf("got %d, want %d", got, want))
+	}
+	g3 := &_ListNum[float64]{nil, 13.5}
+	g2 := &_ListNum[float64]{g3, 1.2}
+	g1 := &_ListNum[float64]{g2, 4.5}
+	if got, want := g1.ClippedLargest(), 4.5; got != want {
+		panic(fmt.Sprintf("got %f, want %f", got, want))
+	}
+}