typedsync: Bring up to being a mostly-drop-in replacement for Go 1.20 sync

1 files changed, 38 insertions, 0 deletions

diff --git a/typedsync/cond.go b/typedsync/cond.go
new file mode 100644
index 0000000..00d3164
--- /dev/null
+++ b/typedsync/cond.go
@@ -0,0 +1,38 @@
+// Copyright (C) 2023  Luke Shumaker <lukeshu@lukeshu.com>
+//
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+package typedsync
+
+import (
+	"sync"
+)
+
+// Cond is a type-safe equivalent of the standard library's sync.Cond.
+//
+// See the [sync.Cond documentation] for full details.
+//
+// [sync.Cond documentation]: https://pkg.go.dev/sync#Cond
+type Cond[T Locker] struct {
+	L     T
+	inner sync.Cond
+}
+
+func NewCond[T Locker](l T) *Cond[T] {
+	return &Cond[T]{L: l}
+}
+
+func (c *Cond[T]) Broadcast() {
+	c.inner.L = c.L
+	c.inner.Broadcast()
+}
+
+func (c *Cond[T]) Signal() {
+	c.inner.L = c.L
+	c.inner.Signal()
+}
+
+func (c *Cond[T]) Wait() {
+	c.inner.L = c.L
+	c.inner.Wait()
+}