args.go
func (a *Args) Set(key, value string) {
	a.args = setArg(a.args, key, value, argsHasValue)
}
func (a *Args) Set(key, value string) {
	a.args = setArg(a.args, key, value, argsHasValue)
}
func ( a * Args ) Set ( key , value string ) { a . args = setArg ( a . args , key , value , argsHasValue ) }
// Set sets 'key=value' argument.
Set sets key = value argument .