argparse

README

Examples

you can check more examples here

basic example

package main

import (
	"fmt"
	"os"

	"github.com/sloweax/argparse"
)

// $ go run . -v -s abc
// verbose=true short=abc long= positional=

// $ go run . -vs xyz
// verbose=true short=xyz long= positional=

// $ go run . -s abc --long 123 xyz
// verbose=false short=abc long=123 positional=xyz

// $ go run . --help
// usage: ./basic [-h] [-v] [-s var] [--long var] [positional]
//
// options:
//     -h, --help     shows usage and exits
//     -v
//     -s var
//     --long var
//     positional

func main() {
	parser := argparse.NewWithDefaults()

	verbose := false
	short := ""
	long := ""
	positional := ""

	parser.AddOption(argparse.Bool("v", &verbose))
	parser.AddOption(argparse.String("s", &short))
	parser.AddOption(argparse.String("long", &long))
	parser.AddOption(argparse.StringPositional("positional", &positional))

	if err := parser.ParseArgs(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}

	fmt.Printf("verbose=%v short=%v long=%v positional=%v\n", verbose, short, long, positional)
}

from struct example

package main

import (
	"fmt"
	"os"

	"github.com/sloweax/argparse"
)

type MyStruct struct {
	// alias accepts a comma separated list of names
	Flag       bool   `alias:"f"`
	LongName   string `alias:"l"`
	Positional string `type:"positional" required:"true"`
	// if name is not specified. it will be auto generated based on field name
	BadNameForOption string `name:"nice-name"`
	// dont add the option below
	Ignored string `ignored:"true"`
}

// go run . --long-name abc -f 123 --nice-name test
// Flag=true
// LongName=abc
// Positional=123
// BadNameForOption=test

func main() {
	ms := MyStruct{}
	parser := argparse.FromStruct(&ms)

	if err := parser.ParseArgs(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}

	fmt.Printf("Flag=%v\n", ms.Flag)
	fmt.Printf("LongName=%v\n", ms.LongName)
	fmt.Printf("Positional=%v\n", ms.Positional)
	fmt.Printf("BadNameForOption=%v\n", ms.BadNameForOption)
}

subparser example

package main

import (
	"fmt"
	"os"

	"github.com/sloweax/argparse"
)

// $ go run . --prefix cool- add file
// adding file cool-file

// $ go run . --prefix very- del bad-file
// deleting file very-bad-file

func main() {
	parser := argparse.New()
	add_parser := argparse.New()
	del_parser := argparse.New()

	parser.AddSubParser("add", add_parser)
	parser.AddSubParser("del", del_parser)

	prefix := ""
	parser.AddOption(argparse.String("prefix", &prefix))

	file := ""
	add_parser.AddOption(argparse.StringPositional("file", &file).SetRequired(true))
	del_parser.AddOption(argparse.StringPositional("file", &file).SetRequired(true))

	if err := parser.ParseArgs(); err != nil {
		fmt.Println(err)
		os.Exit(1)
	}

	switch parser.SubParser {
	case add_parser:
		fmt.Printf("adding file %s\n", prefix+file)
	case del_parser:
		fmt.Printf("deleting file %s\n", prefix+file)
	default:
		fmt.Println("nothing to do")
	}
}

Documentation

Index

• Variables
• type ArgParser
  • func FromStruct(s any) *ArgParser
  • func New() *ArgParser
  • func NewWithDefaults() *ArgParser
  • func (a *ArgParser) AddOption(opt Option)
  • func (a *ArgParser) AddOptionWithAlias(opt Option, aliases ...string)
  • func (a *ArgParser) AddSubParser(name string, p *ArgParser)
  • func (a *ArgParser) Aliases() [][]*Option
  • func (a *ArgParser) LoadStruct(s any)
  • func (a *ArgParser) Options() []*Option
  • func (a *ArgParser) Parse(args ...string) error
  • func (a *ArgParser) ParseArgs() error
  • func (a *ArgParser) String() string
  • func (a *ArgParser) Unparceable(callback func(*Context, string, error))
  • func (a *ArgParser) Usage() string
• type Context
  • func (c *Context) Abort()
  • func (c *Context) AbortWithError(err error)
  • func (c *Context) Next() string
  • func (c *Context) NextN(n int) []string
  • func (c *Context) Option() *Option
  • func (c *Context) Peek() string
  • func (c *Context) Remain() []string
  • func (c *Context) Remaining() int
  • func (c *Context) Skip(n int)
• type Option
  • func Bool(name string, v *bool) Option
  • func Func(name string, f func()) Option
  • func Int(name string, v *int) Option
  • func IntPositional(name string, v *int) Option
  • func Sscanf(name string, format string, v ...any) Option
  • func String(name string, v *string) Option
  • func StringAddr(name string, v **string) Option
  • func StringAddrPositional(name string, v **string) Option
  • func StringAppend(name string, v *[]string) Option
  • func StringAppendPositional(name string, v *[]string) Option
  • func StringPositional(name string, v *string) Option
  • func StringRest(name string, v *[]string) Option
  • func StringRestPositional(name string, v *[]string) Option
  • func Uint(name string, v *uint) Option
  • func (o Option) SetAll(required bool, description, metavar string) Option
  • func (o Option) SetDescription(val string) Option
  • func (o Option) SetMetavar(val string) Option
  • func (o Option) SetPositional(val bool) Option
  • func (o Option) SetRequired(val bool) Option
  • func (o *Option) String() string

Variables

var (
	BreakLineThreshold = 80
)

Types

type ArgParser

type ArgParser struct {
	Name        string
	Description string

	// selected subparser
	SubParser     *ArgParser
	SubParserName string
	// contains filtered or unexported fields
}

func FromStruct

func FromStruct(s any) *ArgParser

func New

func New() *ArgParser

func NewWithDefaults

func NewWithDefaults() *ArgParser

func (*ArgParser) AddOption

func (a *ArgParser) AddOption(opt Option)

func (*ArgParser) AddOptionWithAlias

func (a *ArgParser) AddOptionWithAlias(opt Option, aliases ...string)

func (*ArgParser) AddSubParser

func (a *ArgParser) AddSubParser(name string, p *ArgParser)

func (*ArgParser) Aliases

func (a *ArgParser) Aliases() [][]*Option

func (*ArgParser) LoadStruct

func (a *ArgParser) LoadStruct(s any)

func (*ArgParser) Options

func (a *ArgParser) Options() []*Option

func (*ArgParser) Parse

func (a *ArgParser) Parse(args ...string) error

func (*ArgParser) ParseArgs

func (a *ArgParser) ParseArgs() error

func (*ArgParser) String

func (a *ArgParser) String() string

func (*ArgParser) Unparceable

func (a *ArgParser) Unparceable(callback func(*Context, string, error))

func (*ArgParser) Usage

func (a *ArgParser) Usage() string

type Context

type Context struct {
	// contains filtered or unexported fields
}

func (*Context) Abort

func (c *Context) Abort()

func (*Context) AbortWithError

func (c *Context) AbortWithError(err error)

func (*Context) Next

func (c *Context) Next() string

func (*Context) NextN

func (c *Context) NextN(n int) []string

func (*Context) Option

func (c *Context) Option() *Option

return current option

func (*Context) Peek

func (c *Context) Peek() string

func (*Context) Remain

func (c *Context) Remain() []string

func (*Context) Remaining

func (c *Context) Remaining() int

func (*Context) Skip

func (c *Context) Skip(n int)

type Option

type Option struct {
	Name        string
	Nargs       int
	Positional  bool
	Callback    func(ctx *Context, args ...string)
	Required    bool
	Metavar     string
	Description string
	// contains filtered or unexported fields
}

func Bool

func Bool(name string, v *bool) Option

func Func

func Func(name string, f func()) Option

func Int

func Int(name string, v *int) Option

func IntPositional

func IntPositional(name string, v *int) Option

func Sscanf

func Sscanf(name string, format string, v ...any) Option

func String

func String(name string, v *string) Option

func StringAddr

func StringAddr(name string, v **string) Option

func StringAddrPositional

func StringAddrPositional(name string, v **string) Option

func StringAppend

func StringAppend(name string, v *[]string) Option

func StringAppendPositional

func StringAppendPositional(name string, v *[]string) Option

func StringPositional

func StringPositional(name string, v *string) Option

func StringRest

func StringRest(name string, v *[]string) Option

func StringRestPositional

func StringRestPositional(name string, v *[]string) Option

func Uint

func Uint(name string, v *uint) Option

func (Option) SetAll

func (o Option) SetAll(required bool, description, metavar string) Option

func (Option) SetDescription

func (o Option) SetDescription(val string) Option

func (Option) SetMetavar

func (o Option) SetMetavar(val string) Option

func (Option) SetPositional

func (o Option) SetPositional(val bool) Option

func (Option) SetRequired

func (o Option) SetRequired(val bool) Option

func (*Option) String

func (o *Option) String() string