README
¶
getopt
Package getopt provides a minimal, getopt(3)-like argument parsing implementation with POSIX compatible semantics.
Example
package main
import (
"fmt"
"github.com/dmgk/getopt"
)
// go run example.go -ba42 -v -z -- -w arg1 arg2
func main() {
// -a requires an argument
// -b and -v have no arguments
// -z may have an optional argument
opts, err := getopt.New("a:bz::v")
if err != nil {
fmt.Printf("error creating scanner: %s\n", err)
return
}
for opts.Scan() {
opt, err := opts.Option()
if err != nil {
fmt.Printf("%s: error parsing option: %s\n", opts.ProgramName(), err)
continue
}
if opt.HasArg() {
fmt.Printf("%s: got option %q with arg %q\n", opts.ProgramName(), opt.Opt, opt)
} else {
fmt.Printf("%s: got option %q\n", opts.ProgramName(), opt.Opt)
}
}
fmt.Printf("%s: remaining arguments: %v\n", opts.ProgramName(), opts.Args())
}
$ go run example.go -ba42 -v -z -- -w arg1 arg2
example: got option 'b'
example: got option 'a' with arg "42"
example: got option 'v'
example: got option 'z'
example: remaining arguments: [-w arg1 arg2]
Documentation
¶
Overview ¶
Package getopt provides a minimal, getopt(3)-like argument parsing implementation with POSIX compatible semantics.
Index ¶
- type InvalidOptionError
- type MissingArgumentError
- type Option
- func (o *Option) Float32() (float32, error)
- func (o *Option) Float64() (float64, error)
- func (o *Option) HasArg() bool
- func (o *Option) Int() (int, error)
- func (o *Option) Int32() (int32, error)
- func (o *Option) Int64() (int64, error)
- func (o *Option) String() string
- func (o *Option) Uint() (uint, error)
- func (o *Option) Uint32() (uint32, error)
- func (o *Option) Uint64() (uint64, error)
- type Scanner
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type InvalidOptionError ¶
type InvalidOptionError byte
InvalidOptionError is returned when scanner encounters an option not listed in optstring.
func (InvalidOptionError) Error ¶
func (e InvalidOptionError) Error() string
type MissingArgumentError ¶
type MissingArgumentError byte
MissingArgumentError is returned when option is missing a required argument.
func (MissingArgumentError) Error ¶
func (e MissingArgumentError) Error() string
type Scanner ¶
type Scanner struct {
// contains filtered or unexported fields
}
Scanner contains option scanner data.
func New ¶
New returns a new options scanner using os.Args as the command line arguments source. The option string optstring may contain the following elements: individual characters, and characters followed by a colon to indicate an option argument is to follow. If optstring starts with ':' then all option argument are treated as optional.
func NewArgv ¶
New returns a new options scanner using passed argv as the command line argument source. The option string optstring may contain the following elements: individual characters, and characters followed by a colon to indicate an option argument is to follow. If optstring starts with ':' then all option argument are treated as optional.
Example ¶
scanner, err := NewArgv("a:bz::v", []string{"getopt", "-ba42", "-v", "-z", "--", "-w", "arg1", "arg2"})
if err != nil {
panic("error creating scanner: " + err.Error())
}
for scanner.Scan() {
opt, err := scanner.Option()
if err != nil {
panic("error: " + err.Error())
}
if opt.HasArg() {
fmt.Printf("%s: got option %q with arg %q\n", scanner.ProgramName(), opt.Opt, opt)
} else {
fmt.Printf("%s: got option %q\n", scanner.ProgramName(), opt.Opt)
}
}
fmt.Printf("%s: remaining arguments: %q\n", scanner.ProgramName(), scanner.Args())
Output: getopt: got option 'b' getopt: got option 'a' with arg "42" getopt: got option 'v' getopt: got option 'z' getopt: remaining arguments: ["-w" "arg1" "arg2"]
func (*Scanner) Option ¶
Option returns the next option or an error when it encounters an unknown option or an option that is missing a required argument. If optstring starts with ':' then all arguments are treated as optional and missing arguments do not cause errors.
func (*Scanner) ProgramName ¶
ProgramName returns basename of argv[0].
Source Files