text/template: provide example of overwriting template func after parse
This example illustrates how to overwrite a template function after parsing a template.
This example is intended to clarify the point made in the template.Funcs docstring
that "[i]t is legal to overwrite elements of the map."
Change-Id: Ibded05974d580c54a24fcc16687fd52ce21133ff
GitHub-Last-Rev:
ef19a221ab44f47695c27b3114281112231a1b42
GitHub-Pull-Request: golang/go#72094
Reviewed-on: https://go-review.googlesource.com/c/go/+/654416
Reviewed-by: Junyang Shao <shaojunyang@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>