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flag

package module

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Versions in this module

v1

v1.25.0

Aug 18, 2025

v1.24.2

Apr 25, 2025

Changes in this version

+ func BoolFunc(name, usage string, fn func(string) error)

+ func TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, ...)

type FlagSet

+ func (f *FlagSet) BoolFunc(name, usage string, fn func(string) error)

+ func (f *FlagSet) TextVar(p encoding.TextUnmarshaler, name string, value encoding.TextMarshaler, ...)

v1.16.0

Apr 2, 2021

Changes in this version

+ func Func(name, usage string, fn func(string) error)

type FlagSet

+ func (f *FlagSet) Func(name, usage string, fn func(string) error)

v1.15.0

Aug 25, 2020

Changes in this version

+ var CommandLine = NewFlagSet(os.Args[0], ExitOnError)

+ var DefaultConfigFlagname = "config"

+ var EnvironmentPrefix = ""

+ var ErrHelp = errors.New("flag: help requested")

+ var Usage = func()

+ func Arg(i int) string

+ func Args() []string

+ func Bool(name string, value bool, usage string) *bool

+ func BoolVar(p *bool, name string, value bool, usage string)

+ func Duration(name string, value time.Duration, usage string) *time.Duration

+ func DurationVar(p *time.Duration, name string, value time.Duration, usage string)

+ func Float64(name string, value float64, usage string) *float64

+ func Float64Var(p *float64, name string, value float64, usage string)

+ func Int(name string, value int, usage string) *int

+ func Int64(name string, value int64, usage string) *int64

+ func Int64Var(p *int64, name string, value int64, usage string)

+ func IntVar(p *int, name string, value int, usage string)

+ func NArg() int

+ func NFlag() int

+ func Parse()

+ func Parsed() bool

+ func PrintDefaults()

+ func Set(name, value string) error

+ func String(name string, value string, usage string) *string

+ func StringVar(p *string, name string, value string, usage string)

+ func Uint(name string, value uint, usage string) *uint

+ func Uint64(name string, value uint64, usage string) *uint64

+ func Uint64Var(p *uint64, name string, value uint64, usage string)

+ func UintVar(p *uint, name string, value uint, usage string)

+ func UnquoteUsage(flag *Flag) (name string, usage string)

+ func Var(value Value, name string, usage string)

+ func Visit(fn func(*Flag))

+ func VisitAll(fn func(*Flag))

+ type ErrorHandling int

+ const ContinueOnError

+ const ExitOnError

+ const PanicOnError

+ type Flag struct

+ DefValue string

+ Name string

+ Usage string

+ Value Value

+ func Lookup(name string) *Flag

+ type FlagSet struct

+ Usage func()

+ func NewFlagSet(name string, errorHandling ErrorHandling) *FlagSet

+ func NewFlagSetWithEnvPrefix(name string, prefix string, errorHandling ErrorHandling) *FlagSet

+ func (f *FlagSet) Arg(i int) string

+ func (f *FlagSet) Args() []string

+ func (f *FlagSet) Bool(name string, value bool, usage string) *bool

+ func (f *FlagSet) BoolVar(p *bool, name string, value bool, usage string)

+ func (f *FlagSet) Duration(name string, value time.Duration, usage string) *time.Duration

+ func (f *FlagSet) DurationVar(p *time.Duration, name string, value time.Duration, usage string)

+ func (f *FlagSet) ErrorHandling() ErrorHandling

+ func (f *FlagSet) Float64(name string, value float64, usage string) *float64

+ func (f *FlagSet) Float64Var(p *float64, name string, value float64, usage string)

+ func (f *FlagSet) Init(name string, errorHandling ErrorHandling)

+ func (f *FlagSet) Int(name string, value int, usage string) *int

+ func (f *FlagSet) Int64(name string, value int64, usage string) *int64

+ func (f *FlagSet) Int64Var(p *int64, name string, value int64, usage string)

+ func (f *FlagSet) IntVar(p *int, name string, value int, usage string)

+ func (f *FlagSet) Lookup(name string) *Flag

+ func (f *FlagSet) NArg() int

+ func (f *FlagSet) NFlag() int

+ func (f *FlagSet) Name() string

+ func (f *FlagSet) Output() io.Writer

+ func (f *FlagSet) Parse(arguments []string) error

+ func (f *FlagSet) ParseEnv(environ []string) error

+ func (f *FlagSet) ParseFile(path string) error

+ func (f *FlagSet) Parsed() bool

+ func (f *FlagSet) PrintDefaults()

+ func (f *FlagSet) Set(name, value string) error

+ func (f *FlagSet) SetOutput(output io.Writer)

+ func (f *FlagSet) String(name string, value string, usage string) *string

+ func (f *FlagSet) StringVar(p *string, name string, value string, usage string)

+ func (f *FlagSet) Uint(name string, value uint, usage string) *uint

+ func (f *FlagSet) Uint64(name string, value uint64, usage string) *uint64

+ func (f *FlagSet) Uint64Var(p *uint64, name string, value uint64, usage string)

+ func (f *FlagSet) UintVar(p *uint, name string, value uint, usage string)

+ func (f *FlagSet) Var(value Value, name string, usage string)

+ func (f *FlagSet) Visit(fn func(*Flag))

+ func (f *FlagSet) VisitAll(fn func(*Flag))

+ type Getter interface

+ Get func() interface{}

+ type Value interface

+ Set func(string) error

+ String func() string

v1.7.4-pre

Nov 23, 2016

v1.7.4-alpha

Dec 28, 2016