func (f *Flags) HasMatch() bool {
	return f.ShowHelp() || f.ShowVersion()
}
HasMatch returns whether or not the supplied args are matches. For example, passing `--help` will match, or some
unknown parameter, but passing nothing will not.
package main
import (
	"flag"
	"fmt"
	"io"
	gendoc "github.com/pseudomuto/protoc-gen-doc"
)
const helpMessage = `
This is a protoc plugin that is used to generate documentation from your protobuf files. Invocation is controlled by
using the doc_opt and doc_out options for protoc.
EXAMPLE: Generate HTML docs
protoc --doc_out=. --doc_opt=html,index.html protos/*.proto
EXAMPLE: Exclude file patterns
protoc --doc_out=. --doc_opt=html,index.html:google/*,somedir/* protos/*.proto
EXAMPLE: Use a custom template
protoc --doc_out=. --doc_opt=custom.tmpl,docs.txt protos/*.proto
EXAMPLE: Generate docs relative to source protos
protoc --doc_out=. --doc_opt=html,index.html,source_relative protos/*.proto
See https: 
`
func Version() string {
	return gendoc.VERSION
}
type Flags struct {
	appName     string
	flagSet     *flag.FlagSet
	err         error
	showHelp    bool
	showVersion bool
	writer      io.Writer
}
func (f *Flags) Code() int {
	if f.err != nil {
		return 1
	}
	return 0
}