time: rewrite ExampleDuration_Nanoseconds to be more idiomatic.

Fix the punctuation and use the proper units for microseconds,
while explaining the incorrect but common variant 'us'.

Change-Id: I9e96694ef27ab4761efccd8616ac7b6700f60d39
Reviewed-on: https://go-review.googlesource.com/c/163917
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/time/example_test.go b/src/time/example_test.go
index a3532584ef587792c56b006d721f824bddbd96f9..3b3c88e6af94b0b192e8baca33e87ffa855564d1 100644 (file)
--- a/src/time/example_test.go
+++ b/src/time/example_test.go
@@ -113,9 +113,14 @@ func ExampleDuration_Minutes() {
 }
 
 func ExampleDuration_Nanoseconds() {
-       u, _ := time.ParseDuration("1us")
-       fmt.Printf("one microsecond has %d nanoseconds.", u.Nanoseconds())
-       // Output: one microsecond has 1000 nanoseconds.
+       u, _ := time.ParseDuration("1µs")
+       fmt.Printf("One microsecond is %d nanoseconds.\n", u.Nanoseconds())
+       // The package also accepts the incorrect but common prefix u for micro.
+       v, _ := time.ParseDuration("1us")
+       fmt.Printf("One microsecond is %6.2e seconds.\n", v.Seconds())
+       // Output:
+       // One microsecond is 1000 nanoseconds.
+       // One microsecond is 1.00e-06 seconds.
 }
 
 func ExampleDuration_Seconds() {