Flag2
A more traditional flag library for the go programming language
What?
A more traditional flag library for the Go programming language. I also have a long history with Python, so the implimentation code looks similar to Python's argparse class.
Why?
I did not like how the flag library that comes with Go parses command line flags.
Differences
-
You can define full word flags with the
--prefix. You can define single character flags with the-prefix. -
Example of a full word flag:
--help -
Example of a single character flag:
-h -
Single character strings can be grouped, but only for boolean types:
-abcdis essentially-a, -b, -c, -d- This only works for boolean type flags
-
--denotes the end of the command line flag options- Everything to the right of
--will not be counted as flags
- Everything to the right of
Getting started
To install: go get github.com/ProfOak/flag2
package main
import (
"os"
"fmt"
"github.com/ProfOak/flag2"
)
func main() {
f := flag2.NewFlag()
// short flag, long flag, description, default argument
f.AddString("n", "name", "this flag wants a name as input", "billy")
f.AddBool("b", "bool", "this flag will store true", false)
// a help flag is added during the parse step
options, args := f.Parse(os.Args)
// A usage method is provided, with details about each flag
// unfortunate side effect of interfaces
if options["help"] == true {
f.Usage()
}
fmt.Println()
if options["name"] != nil {
fmt.Println("The name is:", options["name"])
}
fmt.Println()
fmt.Println("===== FINAL RESULTS =====")
fmt.Println("Options:", options)
fmt.Println("Args:", args)
}
The result of running this program:
go run main.go -b -n ProfOak Extra args
--- Bools ---
-b, --bool this flag will store true
-h, --help Display this message and exit
--- Strings ---
-n, --name this flag wants a name as input
Name is: ProfOak
===== FINAL RESULTS =====
Options: map[help:true bool:true name:ProfOak]
Args: [Extra args]
Reference ./test/test.go for a more detailed example.