cmd/godoc: clearer comments in FormatSelections

R=golang-dev, rsc
CC=golang-dev
https://golang.org/cl/6561073

src/cmd/godoc/format.go

@@ -54,6 +54,8 @@ type SegmentWriter func(w io.Writer, text []byte, selections int)
 // Selection is ignored.
 //
 func FormatSelections(w io.Writer, text []byte, lw LinkWriter, links Selection, sw SegmentWriter, selections ...Selection) {
+	// If we have a link writer, make the links
+	// selection the last entry in selections
 	if lw != nil {
 		selections = append(selections, links)
 	}
@@ -109,7 +111,7 @@ func FormatSelections(w io.Writer, text []byte, lw LinkWriter, links Selection,
 		}
 		// determine the kind of segment change
 		if lw != nil && index == len(selections)-1 {
-			// we have a link segment change:
+			// we have a link segment change (see start of this function):
 			// format the previous selection segment, write the
 			// link tag and start a new selection segment
 			segment(offs)