1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
|
## Update 6th December, 2023
The v2 of this library has been released, and you should probably use
that instead:
```sh
$ go get -u git.sr.ht/~mango/opts/v2
```
# Opts
Opts is a simple Go library implementing unicode-aware getopt(3)- and
getopt_long(3) flag parsing in Go. For details, check out the godoc
documentation.
Note that unlike the `getopt()` C function, the ‘:’ and ‘?’ flags are not
returned on errors — the errors are instead returned via the `err` return
value of `opts.Get()` and `opts.GetLong()`. Additionally, a leading ‘:’
in the opt-string provided to `opts.Get()` is not supported; you are
responsible for your own I/O.
## Example Usage
The following demonstrates an example usage of the `opts.Get()` function…
```go
package main
import (
"fmt"
"os"
"git.sr.ht/~mango/opts/v2"
)
func usage() {
fmt.Fprintf(os.Stderr, "Usage: %s [-ßλ] [-a arg]\n", os.Args[0])
os.Exit(1)
}
func main() {
flags, rest, err := opts.Get(os.Args, "a:ßλ")
if err != nil {
fmt.Fprintf(os.Stderr, "%s: %s\n", os.Args[0], err)
usage()
}
for _, f := range flags {
switch f.Key {
case 'a':
fmt.Println("-a given with argument", f.Value)
case 'ß':
fmt.Println("-ß given")
case 'λ':
fmt.Println("-λ given")
}
}
fmt.Println("The remaining arguments are:", rest)
}
```
…and the following demonstrates an example usage of the `opts.GetLong()`
function:
```go
package main
import (
"fmt"
"os"
"git.sr.ht/~mango/opts"
)
func usage() {
fmt.Fprintf(os.Stderr, "Usage: %s [-ßλ] [-a arg] [--no-short]\n", os.Args[0])
os.Exit(1)
}
func main() {
// The fourth long-option has no short-option equivalent
flags, rest, err := opts.GetLong(os.Args, []opts.LongOpt{
{Short: 'a', Long: "add", Arg: opts.Required},
{Short: 'ß', Long: "sheiße", Arg: opts.None},
{Short: 'λ', Long: "λεωνίδας", Arg: opts.None},
{Short: -1, Long: "no-short", Arg: opts.None},
})
if err != nil {
fmt.Fprintf(os.Stderr, "%s: %s\n", os.Args[0], err)
usage()
}
for _, f := range flags {
switch f.Key {
case 'a':
fmt.Println("-a or --add given with argument", f.Value)
case 'ß':
fmt.Println("-ß or --sheiße given")
case 'λ':
fmt.Println("-λ or --λεωνίδας given")
case -1:
fmt.Println("--no-short given")
}
}
// The remaining arguments
fmt.Println("The remaining arguments are:", rest)
}
```
|