encoding/json: update documentation for MarshalIndent

Make arguments semantics clear without the need to look for
json.Indent documentation.

Change-Id: If9adfe9f477a30d426ae83790b0f2578c0a809b7
Reviewed-on: https://go-review.googlesource.com/61670
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/encoding/json/example_test.go b/src/encoding/json/example_test.go
index 2bbc292c6d..39b3231850 100644
--- a/src/encoding/json/example_test.go
+++ b/src/encoding/json/example_test.go
@@ -273,3 +273,22 @@ func ExampleIndent() {
 	// =	}
 	// =]
 }
+
+func ExampleMarshalIndent() {
+	data := map[string]int{
+		"a": 1,
+		"b": 2,
+	}
+
+	json, err := json.MarshalIndent(data, "<prefix>", "<indent>")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println(string(json))
+	// Output:
+	// {
+	// <prefix><indent>"a": 1,
+	// <prefix><indent>"b": 2
+	// <prefix>}
+}