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