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@fujimaki-k
Created October 21, 2025 04:04
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Support both short and long options using a flag
package main
import (
"flag"
"fmt"
)
// usage は、ヘルプメッセージです。
const usage = `
usage go run main.go [-m MESSAGE]
optional arguments:
-m, --message message (default: Fight dayo!)
-v, --version show version
`
const (
// version は、このアプリケーションのバージョン番号です。
version = "1.0.0"
)
var (
// message は、表示するメッセージです。
message = "Fight dayo!"
)
func main() {
flag.StringVar(&message, "m", "message")
flag.StringVar(&message, "message", "message")
flag.Usage = func () {
fmt.Print(usage)
}
flag.Parse()
fmt.Println(message)
}
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