text: package pflag
  
  import (
  	"time"
  )
  
  // -- time.Duration Value
  type durationValue time.Duration
  
  func newDurationValue(val time.Duration, p *time.Duration) *durationValue {
  	*p = val
  	return (*durationValue)(p)
  }
  
  func (d *durationValue) Set(s string) error {
  	v, err := time.ParseDuration(s)
  	*d = durationValue(v)
  	return err
  }
  
  func (d *durationValue) Type() string {
  	return "duration"
  }
  
  func (d *durationValue) String() string { return (*time.Duration)(d).String() }
  
  func durationConv(sval string) (interface{}, error) {
  	return time.ParseDuration(sval)
  }
  
  // GetDuration return the duration value of a flag with the given name
  func (f *FlagSet) GetDuration(name string) (time.Duration, error) {
  	val, err := f.getFlagType(name, "duration", durationConv)
  	if err != nil {
  		return 0, err
  	}
  	return val.(time.Duration), nil
  }
  
  // DurationVar defines a time.Duration flag with specified name, default value, and usage string.
  // The argument p points to a time.Duration variable in which to store the value of the flag.
  func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
  	f.VarP(newDurationValue(value, p), name, "", usage)
  }
  
  // DurationVarP is like DurationVar, but accepts a shorthand letter that can be used after a single dash.
  func (f *FlagSet) DurationVarP(p *time.Duration, name, shorthand string, value time.Duration, usage string) {
  	f.VarP(newDurationValue(value, p), name, shorthand, usage)
  }
  
  // DurationVar defines a time.Duration flag with specified name, default value, and usage string.
  // The argument p points to a time.Duration variable in which to store the value of the flag.
  func DurationVar(p *time.Duration, name string, value time.Duration, usage string) {
  	CommandLine.VarP(newDurationValue(value, p), name, "", usage)
  }
  
  // DurationVarP is like DurationVar, but accepts a shorthand letter that can be used after a single dash.
  func DurationVarP(p *time.Duration, name, shorthand string, value time.Duration, usage string) {
  	CommandLine.VarP(newDurationValue(value, p), name, shorthand, usage)
  }
  
  // Duration defines a time.Duration flag with specified name, default value, and usage string.
  // The return value is the address of a time.Duration variable that stores the value of the flag.
  func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration {
  	p := new(time.Duration)
  	f.DurationVarP(p, name, "", value, usage)
  	return p
  }
  
  // DurationP is like Duration, but accepts a shorthand letter that can be used after a single dash.
  func (f *FlagSet) DurationP(name, shorthand string, value time.Duration, usage string) *time.Duration {
  	p := new(time.Duration)
  	f.DurationVarP(p, name, shorthand, value, usage)
  	return p
  }
  
  // Duration defines a time.Duration flag with specified name, default value, and usage string.
  // The return value is the address of a time.Duration variable that stores the value of the flag.
  func Duration(name string, value time.Duration, usage string) *time.Duration {
  	return CommandLine.DurationP(name, "", value, usage)
  }
  
  // DurationP is like Duration, but accepts a shorthand letter that can be used after a single dash.
  func DurationP(name, shorthand string, value time.Duration, usage string) *time.Duration {
  	return CommandLine.DurationP(name, shorthand, value, usage)
  }
  