Why Go
- Case Studies
  
  Common problems companies solve with Go
- Use Cases
  
  Stories about how and why companies use Go
- Security Policy
  
  How Go can help keep you secure by default
Learn
Docs
- Effective Go
  
  Tips for writing clear, performant, and idiomatic Go code
- Go User Manual
  
  A complete introduction to building software with Go
- Standard library
  
  Reference documentation for Go's standard library
- Release Notes
  
  Learn what's new in each Go release
Packages
Community
- Recorded Talks
  
  Videos from prior events
- Meetups
  
  Meet other local Go developers
- Conferences
  
  Learn and network with Go developers from around the world
- Go blog
  
  The Go project's official blog.
- Go project
  
  Get help and stay informed from Go
- Get connected

flag

package module

Go to main page

Versions in this module

v1

v1.9.0

Jan 24, 2024

v1.1.0

Jun 16, 2023

v0

v0.2.0

May 18, 2024

Changes in this version

+ type Cmd interface

+ Alias func(flags ...string) *flagFeature

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

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

+ Cfg func(cfgs ...string) *flagFeature

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

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

+ Enum func(enums ...string) *flagFeature

+ Env func(envs ...string) *flagFeature

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

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

+ Func func(name, usage string, fn func(string) error, features ...*flagFeature)

+ GetDefaultUsage func() (usage string, err error)

+ GetDefaultUsageLong func() (usage string, err error)

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

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

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

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

+ LoadCfg func(path string) (err error)

+ LoadEnv func(path string) error

+ Name func() string

+ Parse func(arguments []string) error

+ ParseWithoutArgs func(args []string) error

+ Parsed func() bool

+ Set func(name, value string) error

+ String func(name string, value string, usage string, features ...*flagFeature) *string

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

+ SubCmd func(name string, usage string, onCmd func(subCmd Cmd, args []string))

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

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

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

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

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

+ Var func(value Value, name string, usage string, features ...*flagFeature)

+ func OneCmd(name string, errorHandling ErrorHandling) Cmd

+ type Command struct

+ SubCmds map[string]*subCommand

+ Usage func()

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

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

+ func (f *Command) Bool(name string, value bool, usage string, features ...*flagFeature) *bool

+ func (f *Command) BoolVar(p *bool, name string, value bool, usage string, features ...*flagFeature)

+ func (f *Command) Duration(name string, value time.Duration, usage string, features ...*flagFeature) *time.Duration

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

+ func (f *Command) ErrorHandling() ErrorHandling

+ func (f *Command) Float64(name string, value float64, usage string, features ...*flagFeature) *float64

+ func (f *Command) Float64Var(p *float64, name string, value float64, usage string, features ...*flagFeature)

+ func (f *Command) Func(name, usage string, fn func(string) error, features ...*flagFeature)

+ func (f *Command) GetDefaultUsage() (usage string, err error)

+ func (f *Command) GetDefaultUsageLong() (usage string, err error)

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

+ func (f *Command) Int(name string, value int, usage string, features ...*flagFeature) *int

+ func (f *Command) Int64(name string, value int64, usage string, features ...*flagFeature) *int64

+ func (f *Command) Int64Var(p *int64, name string, value int64, usage string, features ...*flagFeature)

+ func (f *Command) IntVar(p *int, name string, value int, usage string, features ...*flagFeature)

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

+ func (f *Command) NArg() int

+ func (f *Command) NFlag() int

+ func (f *Command) Name() string

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

+ func (f *Command) ParseWithoutArgs(args []string) error

+ func (f *Command) Parsed() bool

+ func (f *Command) PrintDefaults()

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

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

+ func (f *Command) SetUsage(usage string)

+ func (f *Command) String(name string, value string, usage string, features ...*flagFeature) *string

+ func (f *Command) StringVar(p *string, name string, value string, usage string, features ...*flagFeature)

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

+ func (f *Command) Uint(name string, value uint, usage string, features ...*flagFeature) *uint

+ func (f *Command) Uint64(name string, value uint64, usage string, features ...*flagFeature) *uint64

+ func (f *Command) Uint64Var(p *uint64, name string, value uint64, usage string, features ...*flagFeature)

+ func (f *Command) UintVar(p *uint, name string, value uint, usage string, features ...*flagFeature)

+ func (f *Command) Var(value Value, name string, usage string, features ...*flagFeature)

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

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

+ func (fs *Command) Alias(flags ...string) *flagFeature

+ func (fs *Command) Cfg(cfgs ...string) *flagFeature

+ func (fs *Command) Enum(enums ...string) *flagFeature

+ func (fs *Command) Env(envs ...string) *flagFeature

+ func (fs *Command) GetFlagForPtr(ptr interface{}) (*Flag, error)

+ func (fs *Command) LoadCfg(path string) (err error)

+ func (fs *Command) LoadEnv(path string) error

+ func (fs *Command) SubCmd(name string, usage string, fn func(cmd Cmd, args []string))

v0.1.10

Aug 29, 2023

v0.1.9

Jun 24, 2023

Changes in this version

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

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

+ var Usage = CommandLine.Usage

+ func Alias(flags ...string) *flagFeature

+ func Arg(i int) string

+ func Args() []string

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

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

+ func Cfg(cfgs ...string) *flagFeature

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

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

+ func Enum(enums ...string) *flagFeature

+ func Env(envs ...string) *flagFeature

+ func EnvToMap(content string) (map[string]string, error)

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

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

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

+ func GetDefaultUsage() (usage string, err error)

+ func GetDefaultUsageLong() (usage string, err error)

+ func GetFirstSubCommandWithArgs(args []string) (string, []string, bool)

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

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

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

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

+ func JSONToMap(content string) (map[string]interface{}, error)

+ func LoadCfg(path string) (err error)

+ func LoadEnv(path string) error

+ func MainCmd(name string, usage string, errorHandling ErrorHandling, args []string, ...)

+ func MainCmdFs(name string, usage string, errorHandling ErrorHandling, args []string, ...)

+ func MapToJSON(data map[string]interface{}) (string, error)

+ func MapToTOML(data map[string]interface{}) (string, error)

+ func MapToYAML(data map[string]interface{}) (string, error)

+ func NArg() int

+ func NFlag() int

+ func Parse() error

+ func ParseWithoutArgs() error

+ func Parsed() bool

+ func Set(name, value string) error

+ func String(name string, value string, usage string, features ...*flagFeature) *string

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

+ func SubCmd(name string, usage string, fn func(cmd CMD, args []string))

+ func SubCmdFs(name string, usage string, fn func(fs *FlagSet, args []string))

+ func TOMLToMap(content string) (map[string]interface{}, error)

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

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

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

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

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

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

+ func Var(value Value, name string, usage string, features ...*flagFeature)

+ func Visit(fn func(*Flag))

+ func VisitAll(fn func(*Flag))

+ func YAMLToMap(content string) (map[string]interface{}, error)

+ type CMD interface

+ Alias func(flags ...string) *flagFeature

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

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

+ Cfg func(cfgs ...string) *flagFeature

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

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

+ Enum func(enums ...string) *flagFeature

+ Env func(envs ...string) *flagFeature

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

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

+ Func func(name, usage string, fn func(string) error, features ...*flagFeature)

+ GetDefaultUsage func() (usage string, err error)

+ GetDefaultUsageLong func() (usage string, err error)

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

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

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

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

+ LoadCfg func(path string) (err error)

+ LoadEnv func(path string) error

+ Name func() string

+ Parse func(arguments []string) error

+ ParseWithoutArgs func(args []string) error

+ Parsed func() bool

+ Set func(name, value string) error

+ String func(name string, value string, usage string, features ...*flagFeature) *string

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

+ SubCmd func(name string, usage string, fn func(cmd CMD, args []string))

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

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

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

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

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

+ Var func(value Value, name string, usage string, features ...*flagFeature)

+ func NewCmd(name string, usage string, errorHandling ErrorHandling) CMD

+ 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

+ func (f *Flag) Set(s string) error

+ type FlagSet struct

+ SubCmds map[string]*subCommand

+ Usage func()

+ func NewFlagSet(name 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, features ...*flagFeature) *bool

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

+ func (f *FlagSet) Duration(name string, value time.Duration, usage string, features ...*flagFeature) *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, features ...*flagFeature) *float64

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

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

+ func (f *FlagSet) GetDefaultUsage() (usage string, err error)

+ func (f *FlagSet) GetDefaultUsageLong() (usage string, err error)

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

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

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

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

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

+ 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) Parse(arguments []string) error

+ func (f *FlagSet) ParseWithoutArgs(args []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) SetUsage(usage string)

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

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

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

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

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

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

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

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

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

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

+ func (fs *FlagSet) Alias(flags ...string) *flagFeature

+ func (fs *FlagSet) Cfg(cfgs ...string) *flagFeature

+ func (fs *FlagSet) Enum(enums ...string) *flagFeature

+ func (fs *FlagSet) Env(envs ...string) *flagFeature

+ func (fs *FlagSet) GetFlagForPtr(ptr interface{}) (*Flag, error)

+ func (fs *FlagSet) LoadCfg(path string) (err error)

+ func (fs *FlagSet) LoadEnv(path string) error

+ func (fs *FlagSet) SubCmd(name string, usage string, fn func(cmd CMD, args []string))

+ func (fs *FlagSet) SubCmdFs(name string, usage string, fn func(fs *FlagSet, args []string))

+ type Getter interface

+ Get func() any

+ type Value interface

+ Set func(s string) error

+ String func() string