feat: add func Tee

concurrency/channel.go

@@ -125,6 +125,32 @@ func (c *Channel) FanIn(ctx context.Context, channels ...<-chan any) <-chan any
 	return multiplexedStream
 }
 
+// Tee split one chanel into two channels
+func (c *Channel) Tee(ctx context.Context, in <-chan any) (<-chan any, <-chan any) {
+	out1 := make(chan any)
+	out2 := make(chan any)
+
+	go func() {
+		defer close(out1)
+		defer close(out2)
+
+		for val := range c.OrDone(ctx, in) {
+			var out1, out2 = out1, out2
+			for i := 0; i < 2; i++ {
+				select {
+				case <-ctx.Done():
+				case out1 <- val:
+					out1 = nil
+				case out2 <- val:
+					out2 = nil
+				}
+			}
+		}
+	}()
+
+	return out1, out2
+}
+
 // Or merge one or more done channels into one done channel, which is closed when any done channel is closed
 func (c *Channel) Or(channels ...<-chan any) <-chan any {
 	switch len(channels) {