Flag with selectable value

[RedX2501]

First Check

• I added a very descriptive title here.
• I used the GitHub search to find a similar question and didn't find it.
• I searched the Typer documentation, with the integrated search.
• I already searched in Google "How to X in Typer" and didn't find any information.
• I already read and followed all the tutorials in the docs and didn't find an answer.
• I already checked if it is not related to Typer but to Click.

Commit to Help

• I commit to help with one of those options 👆

Example Code

import typer
from enum import Enum

class MyColor(str, Enum):
  RED = "red", # this is basically the best color for 90% of the users
  BLUE = "blue"

app = typer.Typer()

@app.command()
def example(color: Optional[MyColor] = typer.Option(default=None, help="Useful"):
  if color:
    print("Your color is:", color)
  pass

Description

$ app
# Nothing is printed
$ app --color # I'd like for the default color RED to be used
Your color is red
$ app --color blue
Your color is blue

Operating System

Linux

Operating System Details

No response

Typer Version

typer==0.16.1

Python Version

Python 3.8.10

Additional Context

This feature is useful when a certain operation has multiple options but one of them is the preferred choice in most cases.
Forcing the users to actually choose it is not a nice experience.

In there any way to accomplish this right now?

All options that I can pass to Option seem to only apply after it parsed. Even parse expects to have the second value to parse.

This is basically a flag where just providing the option sets the default value but it is allowed to pass also a value to select from. This would also apply to any other Option or Argument type.

[svlandeg]

You can put

typer.Option(default=MyColor.RED, help="...")

for the color to be red by default. If you also want the option to toggle between color or no color, I think you should add an additional boolean flag that decides exactly that.