Multiple CLI Options¶
You can declare a CLI option that can be used multiple times, and then get all the values.
For example, let's say you want to accept several users in a single execution.
For this, use the standard Python typing.List to declare it as a list of str:
from typing import List, Optional
import typer
from typing_extensions import Annotated
def main(user: Annotated[Optional[List[str]], typer.Option()] = None):
if not user:
print(f"No provided users (raw input = {user})")
raise typer.Abort()
for u in user:
print(f"Processing user: {u}")
if __name__ == "__main__":
typer.run(main)
🤓 Other versions and variants
Tip
Prefer to use the Annotated version if possible.
from typing import List, Optional
import typer
def main(user: Optional[List[str]] = typer.Option(None)):
if not user:
print(f"No provided users (raw input = {user})")
raise typer.Abort()
for u in user:
print(f"Processing user: {u}")
if __name__ == "__main__":
typer.run(main)
You will receive the values as you declared them, as a list of str.
Check it:
// The default value is 'None'
$ python main.py
No provided users (raw input = None)
Aborted!
// Now pass a user
$ python main.py --user Camila
Processing user: Camila
// And now try with several users
$ python main.py --user Camila --user Rick --user Morty
Processing user: Camila
Processing user: Rick
Processing user: Morty
Multiple float¶
The same way, you can use other types and they will be converted by Typer to their declared type:
from typing import List
import typer
from typing_extensions import Annotated
def main(number: Annotated[List[float], typer.Option()] = []):
print(f"The sum is {sum(number)}")
if __name__ == "__main__":
typer.run(main)
🤓 Other versions and variants
Tip
Prefer to use the Annotated version if possible.
from typing import List
import typer
def main(number: List[float] = typer.Option([])):
print(f"The sum is {sum(number)}")
if __name__ == "__main__":
typer.run(main)
Check it:
$ python main.py
The sum is 0
// Try with some numbers
$ python main.py --number 2
The sum is 2.0
// Try with some numbers
$ python main.py --number 2 --number 3 --number 4.5
The sum is 9.5
Passing multiple values in a single argument¶
Typer supports passing multiple arguments with a single option, by using the separator parameter in combination with typing.List[T] types.
This feature makes it easy to parse multiple values from a single command-line argument into a list in your application.
To use this feature, define a command-line option that accepts multiple values separated by a specific character (such as a comma). Here's an example of how to implement this:
=== "Python 3.7+"
```Python hl_lines="7"
```
=== "Python 3.7+ non-Annotated"
!!! tip
Prefer to use the `Annotated` version if possible.
```Python hl_lines="6"
```
Check it:
// With no optional CLI argument
$ python main.py
The sum is 0
// With one number argument
$ python main.py --number 2
The sum is 2.0
// With several number arguments, split using the separator defined by the Option argument
$ python main.py --number "2, 3, 4.5"
The sum is 9.5
// You can remove the quotes if no whitespace is added between the numbers
$ python main.py --number 2,3,4.5
The sum is 9.5
// Supports passing the option multiple times. This joins all values to a single list
$ python main.py --number 2,3,4.5 --number 5
The sum is 14.5
!!! warning Only single-character non-whitespace separators are supported.