How can I see the flag's base type?

[jokemanfire]

Such like:
GLOBAL OPTIONS:
--lang value, -l value language for the greeting (default: "english")
--help, -h show help

I want
--lang string, -l string language for the greeting (default: "english")
--help, -h show help

I want the flag type to be show. not "value".

[Skeeve]

Easy.

Try this: https://go.dev/play/p/YGGpVX0_4L4

View Source

package main

import (
	"context"
	"fmt"
	"net/mail"
	"os"
	"time"

	cli "github.com/urfave/cli/v3"
)

func main() {
	cmd := &cli.Command{
		Name:        "greet",
		Version:     "0.1.0",
		Description: "This is how we describe greet the app",
		Authors: []any{
			&mail.Address{Name: "Harrison", Address: "harrison@lolwut.example.com"},
			"Oliver Allen  <oliver@toyshop.example.com>",
		},
		Flags: []cli.Flag{
			&cli.StringFlag{Name: "name", Value: "bob", Usage: "a name (`string`) to say"},
		},
		Arguments: cli.AnyArguments,
		Commands: []*cli.Command{
			{
				Name:        "describeit",
				Aliases:     []string{"d"},
				Usage:       "use it to see a description",
				Description: "This is how we describe describeit the function",
				ArgsUsage:   "[arguments...]",
				Action: func(context.Context, *cli.Command) error {
					fmt.Printf("i like to describe things")
					return nil
				},
			},
		},
	}

	ctx, cancel := context.WithTimeout(context.Background(), 100*time.Millisecond)
	defer cancel()

	// Simulate the command line arguments
	os.Args = []string{"greet", "help"}

	_ = cmd.Run(ctx, os.Args)
}

[jokemanfire]

I have search the document , and i find that https://cli.urfave.org/v2/examples/flags/#placeholder-values .
If there's more convenient method? Because the flag type is directly determinable while I set cli.StringFlag. It's a little inconvenient for me to set type in Usage for every flags. 0.0

[Skeeve]

You don't have to set it for every flag. Only for those where you do not want to have the default.

But i think it's a good idea to write the type in the description anyway.

If you want to have it differently, have a look at the source and make a PR.

cli/flag.go

Line 299 in 7fc43e7

func stringifyFlag(f Flag) string {

Especially here:

cli/flag.go

Line 309 in 7fc43e7

placeholder = defaultPlaceholder

Try to determine the flag's type here and set a different placeholder depending on that.

[jokemanfire]

Thanks I will try!