Custom command-line flags with flag.Func - Alex Edwards

One of my favorite things about the recent Go 1.16 release is a small — but very welcome — addition to the flag package: the flag.Func() function. This makes it much easier to define and use custom command-line flags in your application. For example, if you want to parse a flag like --pause=10s directly into a time.Duration type, or parse --urls="http://example.com http://example.org" directly int