feat: add RepeateFn function

concurrency/channel.go

@@ -53,6 +53,24 @@ func (c *Channel) Repeat(done <-chan any, values ...any) <-chan any {
 	return dataStream
 }
 
+// RepeatFn return a chan, excutes fn repeatly, and put the result into retruned chan
+// until close the `done` channel
+func (c *Channel) RepeatFn(done <-chan any, fn func() any) <-chan any {
+	dataStream := make(chan any)
+
+	go func() {
+		defer close(dataStream)
+		for {
+			select {
+			case <-done:
+				return
+			case dataStream <- fn():
+			}
+		}
+	}()
+	return dataStream
+}
+
 // Take return a chan whose values are tahken from another chan
 func (c *Channel) Take(done <-chan any, valueStream <-chan any, number int) <-chan any {
 	takeStream := make(chan any)

concurrency/channel_test.go

@@ -42,6 +42,28 @@ func TestRepeat(t *testing.T) {
 	assert.Equal(1, <-intStream)
 }
 
+func TestRepeatFn(t *testing.T) {
+	assert := internal.NewAssert(t, "TestRepeatFn")
+
+	done := make(chan any)
+	defer close(done)
+
+	fn := func() any {
+		s := "a"
+		return s
+	}
+	c := NewChannel()
+	dataStream := c.Take(done, c.RepeatFn(done, fn), 3)
+
+	// for v := range dataStream {
+	// 	t.Log(v) //a, a, a
+	// }
+
+	assert.Equal("a", <-dataStream)
+	assert.Equal("a", <-dataStream)
+	assert.Equal("a", <-dataStream)
+}
+
 func TestTake(t *testing.T) {
 	assert := internal.NewAssert(t, "TestRepeat")