Package xflags implements command-line flag parsing and is a compatible alternative to Go's flag package. This package provides higher-order features such as subcommands, positional arguments, required arguments, validation, support for environment variables and others.
Package xflags aims to make composing large, full-featured command line tools as simple and clean as possible. The Builder pattern is employed with method chaining to configure commands and flags declaratively with error checking.
See the docs for comprehensive examples.