Add comments to explain for Dataset

Explains the intended use of ExternalInputChans and ExternalOutputChans.
zfg88287508 · Sep 1, 2016 · be91ca8 · be91ca8
1 parent 0e18f9c
commit be91ca8
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/flow/dataset.go b/flow/dataset.go
@@ -15,6 +15,13 @@ type Dataset struct {
 	Shards              []*DatasetShard
 	Step                *Step
 	ReadingSteps        []*Step
+
+	// External[Input|Output]Chans are channels for reading and outputing
+	// data from and to external sources; meaning that they are not managed
+	// by other Dataset objects.
+	//
+	// They are used to setup in-memory input and output for a flow.
+	// See doChannel() and AddOutput().
 	ExternalInputChans  []reflect.Value
 	ExternalOutputChans []reflect.Value