package cli
import (
"flag"
"fmt"
"strconv"
)
// Apply populates the flag given the flag set and environment
func (f *UintFlag) Apply(set *flag.FlagSet) error {
// set default value so that environment wont be able to overwrite it
f.defaultValue = f.Value
if val, source, found := flagFromEnvOrFile(f.EnvVars, f.FilePath); found {
if val != "" {
valInt, err := strconv.ParseUint(val, f.Base, 64)
if err != nil {
return fmt.Errorf("could not parse %q as uint value from %s for flag %s: %s", val, source, f.Name, err)
}
f.Value = uint(valInt)
f.HasBeenSet = true
for _, name := range f.Names() {
if f.Destination != nil {
set.UintVar(f.Destination, name, f.Value, f.Usage)
continue
set.Uint(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 *UintFlag) GetValue() string {
return fmt.Sprintf("%d", f.Value)
// GetDefaultText returns the default text for this flag
func (f *UintFlag) GetDefaultText() string {
if f.DefaultText != "" {
return f.DefaultText
return fmt.Sprintf("%d", f.defaultValue)
// Get returns the flag’s value in the given Context.
func (f *UintFlag) Get(ctx *Context) uint {
return ctx.Uint(f.Name)
// RunAction executes flag action if set
func (f *UintFlag) RunAction(c *Context) error {
if f.Action != nil {
return f.Action(c, c.Uint(f.Name))
// Uint looks up the value of a local UintFlag, returns
// 0 if not found
func (cCtx *Context) Uint(name string) uint {
if fs := cCtx.lookupFlagSet(name); fs != nil {
return lookupUint(name, fs)
return 0
func lookupUint(name string, set *flag.FlagSet) uint {
f := set.Lookup(name)
if f != nil {
parsed, err := strconv.ParseUint(f.Value.String(), 0, 64)
return uint(parsed)