package cli
import (
"flag"
"fmt"
"strconv"
)
// Uint64Flag is a flag with type uint64
type Uint64Flag struct {
Name string
Aliases []string
Usage string
EnvVars []string
FilePath string
Required bool
Hidden bool
Value uint64
DefaultText string
Destination *uint64
HasBeenSet bool
}
// IsSet returns whether or not the flag has been set through env or file
func (f *Uint64Flag) IsSet() bool {
return f.HasBeenSet
// String returns a readable representation of this value
// (for usage defaults)
func (f *Uint64Flag) String() string {
return FlagStringer(f)
// Names returns the names of the flag
func (f *Uint64Flag) Names() []string {
return flagNames(f.Name, f.Aliases)
// IsRequired returns whether or not the flag is required
func (f *Uint64Flag) IsRequired() bool {
return f.Required
// TakesValue returns true of the flag takes a value, otherwise false
func (f *Uint64Flag) TakesValue() bool {
return true
// GetUsage returns the usage string for the flag
func (f *Uint64Flag) GetUsage() string {
return f.Usage
// IsVisible returns true if the flag is not hidden, otherwise false
func (f *Uint64Flag) IsVisible() bool {
return !f.Hidden
// Apply populates the flag given the flag set and environment
func (f *Uint64Flag) Apply(set *flag.FlagSet) error {
if val, ok := flagFromEnvOrFile(f.EnvVars, f.FilePath); ok {
if val != "" {
valInt, err := strconv.ParseUint(val, 0, 64)
if err != nil {
return fmt.Errorf("could not parse %q as uint64 value for flag %s: %s", val, f.Name, err)
f.Value = valInt
f.HasBeenSet = true
for _, name := range f.Names() {
if f.Destination != nil {
set.Uint64Var(f.Destination, name, f.Value, f.Usage)
continue
set.Uint64(name, f.Value, f.Usage)
return nil
// GetValue returns the flags value as string representation and an empty
// string if the flag takes no value at all.
func (f *Uint64Flag) GetValue() string {
return fmt.Sprintf("%d", f.Value)
// Uint64 looks up the value of a local Uint64Flag, returns
// 0 if not found
func (c *Context) Uint64(name string) uint64 {
if fs := c.lookupFlagSet(name); fs != nil {
return lookupUint64(name, fs)
return 0
func lookupUint64(name string, set *flag.FlagSet) uint64 {
f := set.Lookup(name)
if f != nil {
parsed, err := strconv.ParseUint(f.Value.String(), 0, 64)
return parsed