io: add error check to WriteString Example test
Change-Id: I9ce1c79e5799f205aec3a4dc02645ed26bdc3581
GitHub-Last-Rev:
59b637db0154e55ddfdd55e54b9596dc3a0ad32d
GitHub-Pull-Request: golang/go#44533
Reviewed-on: https://go-review.googlesource.com/c/go/+/295389
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Reviewed-by: Robert Griesemer <gri@golang.org>
Trust: Emmanuel Odeke <emmanuel@orijtech.com>
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Emmanuel Odeke <emmanuel@orijtech.com>
TryBot-Result: Go Bot <gobot@golang.org>